ES2355683T3 - INJECTION INK BY WHITE JET IMPROVED FOR STABILITY OF DISPERSION. - Google Patents

Abstract

An inkjet printing method comprising the steps of: a) providing a white inkjet ink and at least one color inkjet ink to a jet inkjet printer; and b) ejecting the white inkjet ink at a temperature greater than the color inkjet ink on an ink receiver, in which the difference in the ejection temperature between the white inkjet ink and the ink Color jet injection is at least 5 ° C.

Description

Technical field

The present invention relates to inkjet printing methods and inkjet ink cartridges using white inkjet ink.

Prior art

In inkjet printing, small droplets of ink fluid are projected directly onto an ink receiving surface without physical contact 10 between the printing device and the ink receiver. The printing device stores the print data electronically and controls a mechanism to eject the drops as an image. Printing is achieved by moving a printhead through the ink receiver or vice versa or both. fifteen

When the inkjet ink is ejected onto an ink receiver, the ink typically includes a liquid carrier and one or more solids, such as dyes or pigments and polymeric binders. It will be readily understood that the optimum composition of said ink depends on the printing method used and on the nature of the ink receiver to be printed. The 20 ink compositions can be roughly divided into:

• water based, the drying mechanism that involves absorption, penetration and evaporation;

• based on solvent, drying essentially involves evaporation;

• Oil-based, drying implies absorption and penetration; 25

• hot melt or phase change, in which the ink is liquid at the ejection temperature but solid at room temperature and in which the drying is replaced by solidification; Y

• UV curable, in which drying is replaced by polymerization.

 It should be clear that the first three types of ink compositions 30 are more suitable for a receiving medium that is more or less absorbent, while hot melt inks and UV curable inks are normally printed on non-absorbent ink receivers. .

 White jet injection inks are generally used for "surface printing" or "reverse printing" to form an image by reflection on a transparent substrate. In surface printing, a white background is formed on a transparent substrate using a white ink and immediately afterwards, a color image is printed, after which the final image formed is seen from the printed side. In the so-called reverse printing, a color image is formed on a transparent substrate using color inks and then a white ink is applied on the color inks and the final formed image is observed through the transparent substrate. In a preferred embodiment, the 5 color jet inkjet ink is ejected onto the partially cured white inkjet ink. If the white ink is only partially cured, an improved wettability of the color ink on the white ink layer is observed. Partial curing immobilizes the ink on the surface of the substrate. A rapid test can be carried out to determine if the white inkjet ink 10 is partially cured by rubbing a finger or cloth across the printed surface, whereby it is observed that the ink can run or fade onto the surface.

 Pigments with a high refractive index, such as titanium dioxide, are used in white ink to obtain sufficient opacity of the printed layer. Sedimentation of these dense particles in a low viscosity fluid, such as a jet ink, is a real challenge for ink formulators. The problems of sealing the nozzles of the inkjet injection heads and the poor storage stability of the ink are direct consequences of sedimentation and aggregation of white pigments due to the difference in the specific gravity between the pigment particles and the liquid medium of the ink.

 Various approaches have been used that attempt to overcome these problems. One approach is to improve dispersibility. EP 1388578 A (DAINIPPON INK) describes an ultraviolet curable ink composition 25 for recording jet injection comprising titanium oxide, a polymeric dispersant having a basic functional group, a photopolymerizable compound and an initiator of the Light curing, the titanium oxide is treated superficially with silica and alumina and the weight of the silica, which coexists with the titanium oxide, is greater than that of the alumina. 30

 Another approach is to design particles that show less sedimentation. US 4880465 (VIDEOJET) describes a non-pigmented white inkjet ink comprising empty microspheres containing a central hollow region loaded with a liquid capable of diffusing through the walls of said microspheres and having an internal diameter of approximately 35 0.1 to about 0.5 micrometers and an outside diameter of about 0.4 to about 0.1 micrometers. Sedimentation is drastically reduced but the opacity of such a white printed layer remains limited.

 A third approach is the adaptation of the hardware that involves a means of agitation to reduce sedimentation, such as, for example, an agitator in the white ink supply container. However, it is complex and expensive to provide a means of agitation in the print head and the tube 5 from the supply container to the print head.

 It would be desirable to be able to print white layers of quality consisting of a wide variety of ink receivers using a state of the art jet injection printer that does not require any complex or expensive adaptation of the printer, in which the 10 problems of Sedimentation of the pigment in the white inkjet ink is greatly reduced or eliminated.

Objects of the invention

It is an object of the present invention to provide inkjet ink cartridges and improved inkjet printing methods 15 for the problems of sedimentation of the white inkjet ink.

Additional objects of the invention will be apparent from the description hereafter in this document.

Summary of the invention

TiO2 is the white pigment of choice for a white inkjet ink because basically its refractive index, which indicates its coating capacity and therefore opacity, is considerably higher than that of other white pigments (see Table 1).

Table 1

 White pigment

 Refractive Density Index (g / cm3)

 Rutile TiO2

 2.73 4.3

 Anatase TiO2

 2.55 3.9

 Zinc oxide

 2.02 5.6

 White lead

 1.94-2.09 5.5

 Lithopon

 1.84 4.3

 Baryta

 1.64 4.5

 Calcium carbonate

 1.63 2.8

It was discovered that sedimentation problems in inkjet printing could be greatly reduced using higher concentrations of TiO2, leading to a higher viscosity and reducing the viscosity of the ink in the inkjet printer to a level in the that the inkjet ink can be ejected by increasing the ejection temperature. 30

The objects of the present invention have also been made with an inkjet printing method as defined by claim 1.

The objects of the present invention have also been made with a jet injection printer as defined by claim 6.

The objects of the present invention have also been made by use as defined by claim 14.

The advantages and further embodiments of the present invention will be apparent from the following description.

Definitions

The term "dye", as used in the description of the present invention refers to dyes and pigments.

The term "dye", as used in the description of the present invention refers to a dye having a solubility of 10 mg / l or more in the medium in which it is applied and in the corresponding environmental conditions. fifteen

The term "pigment" is defined in DIN 55943, incorporated herein by reference, as a coloring agent that is practically insoluble in the application medium under the corresponding environmental conditions, which therefore has a solubility of less than 10 mg. / l in it. twenty

The term "I.C." It is used in the description of the present application as an abbreviation for Color Index.

The term "UV" is used in the description of the present invention as an abbreviation for ultraviolet radiation.

The term "ultraviolet radiation" as used in the description of the present invention refers to electromagnetic radiation in the wavelength range of 100 to 400 nanometers.

The term "% by weight" is used in the description of the present invention as an abbreviation for% by weight based on the total weight of the ink unless otherwise specified. 30

The term "actinic radiation" as used in the description of the present invention refers to electromagnetic radiation capable of initiating photochemical reactions.

The term "Norrish Type I initiator" as used in the description of the present invention, refers to an initiator that cleaves after excitation, producing the initiator radical immediately.

The term "Norrish Type II initiator" as used in the description of the present invention, refers to an initiator that in its excited state forms free radicals by hydrogen abstraction or electron extraction from a second compound that belongs to the real free radical initiator. The second compound is called co-initiator or synergistic polymerization. Synergists are compounds that contain a carbon atom with at least one hydrogen atom in the α-position relative to a nitrogen atom.

The term "photo-acid generator" as used in the description of the present invention refers to an initiator, which generates an acid or hemi-acid upon exposure to actinic radiation. A photo acid generator is also commonly referred to as a cationic initiator. 10

The term "thermal initiator" as used in the description of the present invention refers to an initiator, which generates initiator species upon exposure to heat.

The term "alkyl" refers to all possible variants for each number of carbon atoms in the alkyl group, that is, for three carbon atoms: n-propyl and isopropyl; for four carbon atoms: n-butyl, isobutyl and tertiary butyl; for five carbon atoms: n-pentyl, 1,1-dimethyl-propyl, 2,2-dimethylpropyl and 2-methyl-butyl, etc.

Inkjet printing methods

The inkjet printing method according to the present invention comprises the steps of:

a) providing a white inkjet ink and at least one color inkjet ink to a jet inkjet printer; Y

b) eject the white inkjet ink at a temperature higher than the color inkjet ink on an ink receiver, 25

wherein the difference in the ejection temperature between the white inkjet ink and the color inkjet ink is at least 5 ° C.

The printhead temperature control is used to reduce sedimentation of a pigment with a refractive index greater than 1.60 in a white inkjet ink.

The difference in the expulsion temperature between the white inkjet ink and the color inkjet ink is preferably at least 5 ° C, more preferably at least 10 ° C, and most preferably at least 15 ° C. 35

The white ink temperature in the printhead is preferably reduced when the images that are printed do not require white ink or when the jet injection printer is not used for more than 24 hours.

In a preferred embodiment, the temperature of the white ink in the printhead is reduced while the printhead of the color jet ink remains at its ejection temperature. 5

The inkjet printing method uses a jet injection ink cartridge comprising at least one color ink and one white ink. The color inkjet ink cartridge preferably comprises at least three color inkjet inks and also a black inkjet ink. Preferably, the three color jet injection inks are a cyan ink, a magenta ink and a yellow ink. Red, green and blue inks are also sometimes used as a jet inkjet cartridge or added to a CMYK inkjet ink cartridge.

The inkjet printing method can also use a so-called "multi-density" color inkjet ink cartridge, which comprises color inkjet inks of the same color but of a different color density. For example, the color inkjet ink cartridge may comprise a "dark magenta" jet ink and a "light magenta" inkjet ink. In a preferred embodiment, the multi-density inkjet ink cartridge comprises jet ink inks of dark and light colors for the magenta and cyan colors. Dark black and light black inks may also be present in a color inkjet ink cartridge. The inkjet inkjet cartridge may comprise two, three, 25 four or more black inks of different shades, a white ink and one or more colorless liquids. The latest inkjet inkjet cartridge is capable of providing very detailed black and white images.

In one embodiment, the inkjet printing method uses a color inkjet ink cartridge comprising one or more 30 colorless liquids. A colorless ink can be used, for example, to enhance the brightness of the printed image or as a primer to improve the adhesion of the ink layers to the ink receiver.

Adhesion can be affected using different porimerizable compounds, surfactants, binders and / or organic solvents. For example, it is known that the adhesion of radiation curable inks is promoted on polyvinyl chloride substrates when one or more monomers that are used are suitable for swelling of the PVC substrate and that they are selected from the group consisting of tetrahydrofurfuryl acrylate, 1,6-hexanediol diacrylate and N-vinyl caprolactam. However, adhesion on polycarbonate substrates is promoted when one or more monomers that are used are suitable for swelling of the polycarbonate substrate and are selected from the group consisting of propoxylated neopentyl glycol diacrylate, 2-phenoxylethyl acrylate, 2- (2-ethoxyethoxy) ethyl acrylate and polyethylene glycol diacrylate. With the radiation curable inkjet printing method according to the present invention, it is not necessary to prepare a "best possible" mixture of monomers suitable for swelling of the polyvinyl chloride substrate and the polycarbonate substrates. Instead, a dedicated monomer mixture consisting predominantly of monomers can be prepared, for example, for swelling of polyvinyl chloride substrates if such a substrate is supplied in the printer.

Jet Injection Printer 15

Industrial inkjet printers generally comprise an ink supply system for supplying ink to an inkjet print head. Inkjet printheads produce drops continuously or on demand. "Continuously" refers to the creation of a continuous stream of drops of ink, for example pressurizing the ink supply. "On demand" differs from "continuous" in that the ink droplets are only ejected from a print head by manipulating a physical process to momentarily overcome the surface tension forces that hold the ink in the print head. The ink is kept in a nozzle, forming a meniscus. The ink remains in place unless some other force exceeds the surface tension forces that are inherent in the liquid. The most common practice is to suddenly increase the pressure in the ink, ejecting it from the nozzle. A category of inkjet print heads of droplets on demand uses the physical phenomenon of electrostriction, a change in the size of the transducer in response to an applied electric field. Electrostriction is stronger in piezoelectric materials and therefore these printheads are referred to as piezoelectric printheads. The very small dimensional change of the piezoelectric material is implemented over a large area to generate a volume change that is large enough to squeeze a drop of ink from a small chamber. A piezo printhead includes a multitude of small ink chambers, arranged in a matrix, each having an individual nozzle and a percentage of transformable wall area to create the volume changes required to eject a drop of ink from of the nozzle, in accordance with the principles of electrostriction.

In a preferred embodiment, the jet injection printer is a drop-on-demand inkjet printing system that has piezoelectric printheads for administering ink droplets to an ink receiver.

The inkjet ink is supplied to the ink ejection chambers of a printhead by means of an ink supply system 10 which first conditions the ink to obtain a fluid operation of the inkjet printhead. Conditioning includes, for example, degassing of the ink and control of the back pressure in the nozzle.

It is known that the presence of air bubbles in the ink chamber of a piezoelectric printhead normally causes operational failure of the printhead. If air is present in the ink chamber, the intended pressure changes resulting from the piezoelectric deformation of part of the walls of the ink chamber will be absorbed through the air, leaving the ink pressure unaffected. The surface tension force of the ink in the nozzle maintains the meniscus and no drops will be ejected from the ink chamber. At the frequencies at which the piezoelectric transducers work on the piezoelectric printheads, that is, in the range kHz to MHz, not only air bubbles but also the air dissolved in the ink can cause the operation to fail as described above In the prior art, the concepts have been described to avoid air bubbles in the ink chamber by creating an air trap upstream of the ink chamber, that is, before the ink enters the ink chamber. The solutions have been proposed in EP 714779 A (CANON) and US 4929963 (HP) in the form of air absorbers or gas separators that allow air bubbles to rise and be evacuated from the ink in an intermediate tank before the ink is supplied to the printhead.

A second point of attention in ink supply systems is the pressure in the nozzle, which is critical for the proper synchronization and proper operation of the print head. Inkjet print heads 35 work best at a slightly negative nozzle pressure or back pressure. In practice, this is usually achieved by maintaining a difference in height between the ink-free surface in a depressurized ink supply tank and the meniscus in the nozzle. That is, the ink-free surface in the depressurized supply tank is gravimetrically maintained a couple of centimeters below the level of the meniscus in the nozzle. This height difference establishes a hydrostatic pressure difference to control the back pressure in the nozzle. In the 5 oscillating printhead configurations the ink supply tank is located off-axis, that is, without scanning, because otherwise the lower position of the ink supply tank in front of the printhead would interfere with the trajectory of print media transport. The flexible tube is used to connect the ink supply tank off the shaft with the print head inside the shaft, as described for example in US 4929963 (HP). During the acceleration and deceleration of the printhead, pressure waves are generated in the ducts that can significantly alter the pressure balance in the meniscus and can lead to the nozzle ooze in case of a decrease in negative pressure, or rupture of the meniscus in case of an increase in negative pressure and the entry of air into the ink channel. Many approaches have been proposed to control back pressure in oscillating printhead applications. A back pressure regulating mechanism in the form of pressure dampers or regulators mounted together with the printhead on the oscillating carriage is described in EP 1120257 A (SEIKO EPSON) and US 6,485,137 (DIGITAL APRION). For accelerations and decelerations of the car above 1 G the response time of these devices is insufficient. In EP 1142713 A (SEIKO EPSON) a depressurized subtank is used. The subtank works as a local ink reservoir near the printhead and is filling intermittently from a main tank located off-axis. The solution provides better control of the back pressure of the nozzle while maintaining a local hydrostatic pressure difference between the ink-free surface of the depressurized subtank and the meniscus. 30

The inkjet printer according to the present invention comprises a means for controlling the temperature independently for a white jet inkjet printhead and one or more color jet inkjet printheads. In a more preferred embodiment, the inkjet printer also comprises a means for controlling back pressure independently for a white inkjet printhead and one more color inkjet printhead.

Inkjet ink receivers

The ink receiver suitable for the inkjet printing method according to the present invention is not limited to any specific type and may be transparent, translucent or opaque. The ink receiver can be colored or metallic. It can be a temporary substrate, for example, to transfer an image to another substrate after printing. Also included are applications such as 3D printing, direct printing on wooden or ceramic doors or panels.

Aqueous inks are generally printed on absorbent ink receptors. Solvent-based jet injection inks and radiation curable inks can also be printed on substantially non-absorbent ink receptors for an aqueous solution. For example, conventional paper is an absorbent ink receiver. On the other hand, a resin coated paper, for example, polyethylene coated paper or polypropylene coated paper, is usually not substantially absorbent.

The ink receiver may comprise a support with at least one ink receiving layer. The ink receiving layer may consist of only a single layer, or alternatively, it may be composed of two, three or more layers. The ink receiving layer may contain one or more polymeric binders and optionally fillers. The ink receiving layer and an optional auxiliary layer, such as a backing layer for anti-curl and / or adhesive purposes, may also contain well-known conventional ingredients, such as a surfactant that functions as coating aids, crosslinking agents, plasticizers. , cationic substances that act as a mordant, light stabilizers, pH adjusters, antistatic agents, biocides, lubricants, bleaching agents and bonding agents.

The ink receiving layer and the optional auxiliary layer or layers can be crosslinked to a certain degree to provide such desired characteristics as water resistance and non-blocking characteristics. Crosslinking is also useful for providing abrasion resistance and resistance to fingerprint formation on the element as a result of handling.

Suitable supports for the ink receiving layers are also 35 suitable ink receivers for solvent-based jet-inks or radiation-curable inks and include polymeric substrates, such as cellulose acetate propionate, cellulose acetate butyrate, polyesters such as polyethylene teraphthalate (PET) and polyethylene naphthalate (PEN); oriented polystyrene (PAHO); oriented nylon (ONy); polypropylene (PP), oriented propylene (OPP); polyvinyl chloride (PVC); and various polyamides, polycarbonates, polyimides, polyolefins, poly (vinyl acetals), polyethers and polysulfonamides, opaque white polyesters and extrusion mixtures of 5 polyethylene and polypropylene teraphthalate. Acrylic resins, phenolic resin, glass and metals can also be used as ink receptors. Other suitable ink receiving materials can be found in Modern Approaches to Wettability: Theory and Applications. Edited by SCHRADER, Malcolm E., et al. New York: Plenum Press, 1992. ISBN 0306439859. 10

The ink receiver can also incorporate mineral particles as fillers, such as, for example, PET containing CaCO3, PET containing TiO2, amorphous PET (APET) and glycolized PET (PETG).

The ink receiver can be provided with a self-adhesive back layer. Examples of self-adhesive PVC ink receivers include 15 MPI ™ vinyls from AVERY-DENNISON, Digital ™ vinyls from METAMARK, white multi-fix ™ digital vinyls from MULTI-FIX and Grafiprint ™ vinyls from GRAFITYP.

Polyester film substrates and especially polyethylene teraphthalate are preferred for certain applications, particularly types with excellent dimensional stability. When such a polyester substrate is used as the ink receiver, an adhesive layer can be used to improve the bonding of the ejected ink layer to the substrate, if it constitutes a substantially non-absorbent ink receptor with the non-adhesive substrate. Adhesive layers useful for this purpose are well known in the photographic art and include, for example, vinylidene chloride polymers such as vinylidene / acrylonitrile chloride / acrylic acid terpolymers or vinylidene chloride / methyl acrylate / acid terpolymers Itaconic Stabilizers, leveling additives, bonding agents, adjusting agents for the physical properties of the film such as waxes can be added to the adhesive layer 30 as needed.

The ink receiver may also be formed from an inorganic material, such as a metal oxide or a metal (for example, aluminum and steel).

Other suitable ink receivers can be selected from the group consisting of cardboard, wood, composite boards, coated plastic, canvas, fabric, glass, vegetable fiber products, leather, magnetic materials and ceramics.

Inkjet inkjet cartridges

The color inkjet ink cartridge according to the present invention comprises a white ink containing a pigment with a refractive index greater than 1.60 and at least one color inkjet ink in which the viscosity of the white 5 inkjet ink is at least 4 mPa.s greater than the viscosity of the color inkjet ink at which the viscosity is measured at 40 ° C with a Brookfield DV-II + Pro at 12 rotations per minute.

A color inkjet ink cartridge according to the present invention preferably comprises a white inkjet ink that is radiation curable or electron jet. In a preferred embodiment the color inks are also curable by radiation or electron jet.

The jet injection inks in a color jet injection ink cartridge according to the present invention are preferably 15 non-aqueous jet injection inks. In a non-aqueous jet ink, the components are present in a dispersion medium that is a non-aqueous liquid at the expulsion temperature.

The term "non-aqueous liquid" refers to a liquid excipient that should not contain water. However, sometimes a small amount may be present, generally less than 5% by weight of water based on the total weight of the ink. This water was not intentionally added but enters the formulation through other components as a contamination, such as, for example, polar organic solvents. Water quantities greater than 5% tend to make non-aqueous water jet inks installable, preferably the water content is less than 1% based on the total weight of the dispersion medium and most preferably no water is present. .

The inkjet inks of a color inkjet ink cartridge according to the present invention may also additionally contain at least one surfactant.

The inkjet inks of a color inkjet ink cartridge according to the present invention may contain at least one humectant to prevent nozzle clogging, due to their ability to reduce the ink evaporation rate . 35

The pigmented jet injection inks according to the present invention may contain at least one synergistic dispersion. A mixture of dispersion synergists may be used to further improve dispersion stability.

The inkjet inks of an ink cartridge according to the present invention is preferably a jet injection ink selected from the group consisting of an ink jet ink based on organic solvent, oil based and curable. The curable inkjet ink is preferably radiation curable.

The viscosity of the inkjet ink is preferably less than 100 mPa.s at 30 ° C and at a shear rate of 100 s-1. The viscosity of the inkjet ink is preferably less than 30 mPa.s, more preferably less than 15 mPa.s and most preferably between 2 and 10 10 mPa.s at a shear rate of 100 s-1 and a temperature of expulsion between 10 and 70 ° C.

The curable inkjet ink may contain as dispersion media monomers, oligomers and / or prepolymers having different degrees of functionality. A mixture may be used that includes combinations of mono-, di-, tri-monomers or higher functionalities, oligomers or prepolymers. A catalyst referred to as an initiator to initiate the polymerization embodiment may be included in the curable jet ink. The initiator may be a thermal initiator, but is preferably a photoinitiator. The photoinitiator requires less energy to activate than the monomers, oligomers and / or prepolymers to form the polymer. The photoinitiator suitable for use in the dispersion of curable pigments may be a Norrish type I initiator, a Norrish type II initiator or a photo acid generator.

The curable inkjet inks of an ink cartridge according to the present invention may also additionally contain at least one inhibitor.

In the most preferred embodiment, the ink cartridge comprises a cyan, magenta, yellow and black jet ink, that is, a CMYK inkjet ink cartridge. 30

A CMYK inkjet ink cartridge can also be expanded with one or more additional inks such as red, green, blue and orange to further expand the color gamut of the image. The CMYK ink cartridge can also be enlarged by combining full density and light density inks of color inks and / or black inks to improve image quality by decreasing granularity.

In another embodiment, the inkjet printing method uses a so-called "multi-density" inkjet ink cartridge comprising color inkjet inks of the same color but of a different color density. For example, the ink cartridge may comprise a "dark magenta" inkjet ink and a "light magenta" inkjet ink. In another preferred embodiment, the "multi-density" inkjet ink cartridge comprises dark and light inkjet inkjet 5 for magenta and cyan colors. Dark black and light black inks may also be present in a jet inkjet cartridge. The inkjet inkjet cartridge may comprise two, three, four or more black inks of different shades, a white ink and one or more colorless liquids. The latest 10 inkjet inkjet cartridge is capable of providing very detailed black and white images.

White inkjet ink

The white inkjet ink comprises a pigment with a refractive index greater than 1.60, preferably greater than 2.00, more preferably greater than 2.50 and most preferably greater than 2.60. Suitable pigments are given in Table 2. White pigments can be used individually or in a combination. Preferably, titanium dioxide is used for the pigment with a refractive index greater than 1.60.

Table 2 20

 I.C. Number

 Chemical Name CAS RN

 White pigment 1

 Lead hydroxide carbonate 1319-46-6

 White pigment 3

 Lead Sulfate 7446-14-2

 White pigment 4

 Zinc Oxide 1314-13-2

 White pigment 5

 Lithopon 1345-05-7

 White pigment 6

 Titanium Dioxide 13463-67-7

 White pigment 7

 Zinc Sulfide 1314-98-3

 White pigment 10

 Barium carbonate 513-77-9

 White pigment 11

 Antimony Trioxide 1309-64-4

 White pigment 12

 Zirconium Oxide 1314-23-4

 White pigment 14

 Bismuth Oxychloride 7787-59-9

 White Pigment 17

 Bismuth Subnitrate 1304-85-4

 White Pigment 18

 Calcium carbonate 471-34-1

 White Pigment 19

 Kaolin 1332-58-7

 White Pigment 21

 Barium Sulfate 7727-43-7

 White pigment 24

 Aluminum hydroxide 21645-51-2

 White Pigment 25

 Calcium Sulfate 7778-18-9

 I.C. Number

 Chemical Name CAS RN

 White Pigment 27

 Siliceous Dioxide 7631-86-9

 White Pigment 28

 Calcium Metasilicate 10101-39-0

 White Pigment 32

 Zinc Phosphate Cement 7779-90-0

Titanium oxide appears in the crystalline forms of anatase type, rutile type and brookite type. The anatase type has a relatively low density and is easily ground into fine particles, while the rutile type has a relatively high refractive index, which shows a high coating capacity. Any of these can be used in this invention. It is preferred to make the greatest possible use of the features and make the selections according to their use. The use of the anatase type that has a low density and a small particle size can achieve superior dispersion stability, ink storage stability and ejectability. At least two different crystalline forms can be used in combination. The combined use of the anatase type and the rutile type that shows a high coating capacity can reduce the total amount of titanium oxide, leading to improved storage stability and ink ejection performance. fifteen

For the surface treatment of titanium oxide, an aqueous treatment or a gas phase treatment is applied and an alumina-silica treatment agent is normally used. Untreated titanium oxide, alumina treated or alumina silica treated can be used.

The value of the average particle diameter of the titanium oxide is preferably from 50 to 500 nm, more preferably from 150 to 400 nm and most preferably from 200 to 350 nm. Sufficient coating capacity cannot be obtained when the average diameter is less than 50 nm and the storage capacity and suitability of the ink jet ejection tend to degrade when the average diameter exceeds 500 nm. 25

The white inkjet ink is preferably curable by radiation or electron jet. To improve adhesion on specific substrates, the white inkjet ink preferably comprises a porimerizable compound selected from the group consisting of isobornyl acrylate, phenoxyethyl acrylate, tetrahydrofurfuryl acrylate, 2- (2-) 2- (2-) acrylate vinyloxyethoxy) ethyl and N-vinylcaprolactam.

The white inkjet ink preferably comprises the white pigment in an amount of at least 26% by weight, more preferably 30% by weight and most preferably 40% by weight of the white pigment based on the total weight of the white inkjet ink.

Color Jet Injection Inks

The color inkjet inks of a color inkjet ink cartridge according to the present invention contain at least one dye. The dyes used in the jet injection inks may be pigments, dyes or a combination thereof. Organic and / or inorganic pigments can be used. The color inkjet inks of the inkjet ink cartridge according to the present invention preferably contain a pigment as a dye. If the dye is not a self-dispersible pigment, the jet injection inks also preferably contain a dispersant, more preferably a polymeric dispersant.

Radiation curable jet injection inks or solvent based jet injection inks preferably contain 15 pigments as colorants.

The pigments in the color jet injection inks may be black, cyan, magenta, yellow, red, orange, violet, blue, green, brown, mixtures thereof and the like.

The color pigment can be chosen from those described by HERBST, Willy, et al. Industrial Organic Pigments, Production, Properties, Applications. 3rd edition. Wiley - VCH, 2004. ISBN 3527305769.

Particularly preferred pigments are Yellow Pigment I.C. 1, 3, 10, 12, 13, 14, 17, 55, 65, 73, 74, 75, 83, 93, 97, 109, 111, 120, 128, 138, 139, 150, 151, 154, 155, 180,185 and 213. 25

Particularly preferred pigments are Yellow Pigment I.C. 120, 151, 154, 175, 180, 181 and 194.

The most preferred yellow pigments are Yellow Pigment I.C. 120, 139, 150 155 and 213.

Particularly preferred pigments are Pigment Red I.C. 17, 22, 30 23, 41, 48: 1, 48: 2, 49: 1, 49: 2, 52: 1, 57: 1, 81: 1, 81: 3, 88, 112, 122, 144, 146 , 149, 169, 170, 175, 176, 184, 185, 188, 202, 206, 207, 210, 216, 221, 248, 251, 254, 255, 264, 270 and 272. To make decorative laminates, the most Preferred are Red Pigment IC 254 and Pigment Red I.C. 266. For other non-aqueous jet injection applications the most preferred pigments 35 are Pigment Red I.C. 122 and Pigment Violet I.C. 19.

Particularly preferred pigments are Violet Pigment I.C. 1, 2, 19, 23, 32, 37 and 39.

Particularly preferred pigments are Pigment Blue I.C. 15: 1, 15: 2, 15: 3, 15: 4, 15: 6, 16, 56, 61 and aluminum phthalocyanine pigments (bridged).

Particularly preferred pigments are Pigment Orange I.C. 5, 13, 16, 34, 40, 43, 59, 66, 67, 69, 71 and 73. 5

Particularly preferred pigments are Green Pigment I.C. 7 and 36.

Particularly preferred pigments are Brown Pigment I.C. 6 and 7.

Suitable pigments include mixed crystals of the particularly preferred pigments 10 indicated above. A commercially available example is Cinquasia ™ Magenta RT-355-D from Ciba Specialty Chemicals.

Carbon black is preferred as a pigment for black jet ink. Suitable black pigment materials include carbon blacks, such as Black Pigment 7 (for example, Carbon 15 Black MA8 ™ from MITSUBISHI CHEMICAL), Regal ™ 400R, Mogul ™ L, Elftex ™ 320 from CABOT Co., or Carbon Black FW18 , Special Black 250, Special Black 350, Special Black 550, Printex ™ 25, Printex ™ 35, Printex ™ 55, Printex ™ 90, Printex ™ 150T from DEGUSSA. Additional examples of suitable pigments are described in US 5389133 (XEROX). twenty

It is also possible to prepare mixtures of pigments in the color jet injection inks. For some applications, a neutral black jet injection ink is preferred and can be obtained, for example, by mixing a black pigment and a cyan pigment in the ink. The inkjet application may also require one or more direct colors, for example, for inkjet printing of containers or textile inkjet printing. Silver and gold are normally desired colors for printing inkjet posters and point of sale display screens.

Non-organic pigments may also be present in color jet injection inks. Particularly preferred pigments are Pigment Metal I.C. 1, 2 and 3. Illustrative examples of inorganic pigments include red (III) iron oxide, cadmium red, ultramarine blue, Prussian blue, chromium oxide green, cobalt green, amber, titanium black and black of synthetic iron.

Generally, the pigments are stabilized in the dispersion medium by dispersing agents, such as dispersants or polymeric surfactants. However, the surface of the pigments can be modified to obtain "self-dispersible" or "self-dispersion" pigments, that is, pigments that are dispersible in the dispersion medium without dispersants.

The pigment particles in the inkjet ink should be small enough to allow free flow of the ink through the inkjet printing device, especially in the ejection nozzles. It is also desirable to use small particles to obtain maximum color intensity and to reduce sedimentation.

The value of the average particle size of the pigment is preferably between 0.050 and 1 µm, preferably between 0.070 and 0.300 µm and particularly preferably between 0.080 and 0.200 µm. Most preferably, the value of the average particle size of the pigment is not more than 0,150 µm. 10

The pigment is preferably used in the pigment dispersion used to prepare the inkjet inks in an amount of 10 to 40% by weight, preferably 15 to 30% by weight based on the total weight of the pigment dispersion. In the inkjet ink the pigment is preferably used in an amount of 0.1 to 20% by weight, preferably 1 to 10% by weight based on the total weight of the inkjet ink.

Suitable dyes for color jet injection inks in the ink cartridge according to the present invention include direct dyes, acid dyes, basic dyes and reactive dyes.

Direct dyes suitable for 20 color jet injection inks include:

• Direct Yellow I.C. 1, 4, 8, 11.12, 24, 26, 27, 28, 33, 39, 44, 50, 58, 85, 86, 100, 110, 120, 132, 142 and 144

• Direct Red I.C. 1, 2, 4, 9, 11, 134, 17, 20, 23, 24, 28, 31, 33, 37, 39, 44, 47, 48, 51, 62, 63, 75, 79, 80, 81, 83, 89, 90, 94, 95, 99, 220, 224, 227 and 25 343

• Direct Blue I.C. 1, 2, 6, 8, 15, 22, 25, 71, 76, 78, 80, 86, 87, 90, 98, 106, 108, 120, 123, 163, 165, 192, 193, 194, 195, 196, 199, 200, 201, 202, 203, 207, 236 and 237

• Direct Black I.C. 2, 3, 7, 17, 19, 22, 32, 38, 51, 56, 62, 71, 74, 75, 77, 30 105, 108, 112, 117, 154 and 195

Acid dyes suitable for color jet injection inks include:

• Acid Yellow I.C. 2, 3, 7, 17, 19, 23, 25, 20, 38, 42, 49, 59, 61, 72 and 99

• Acid Orange I.C. 56 and 64 35

• Acid red I.C. 1, 8, 14, 18, 26, 32, 37, 42, 52, 57, 72, 74, 80, 87, 115, 119, 131, 133, 134, 143, 154, 186, 249, 254 and 256

• Violet acid I.C. 11, 34 and 75

• Acid blue I.C. 1, 7, 9, 29, 87, 126, 138, 171, 175, 183, 234, 236 and 249

• Acid green I.C. 9, 12, 19, 27 and 41

• Acid black I.C. 1, 2, 7, 24, 26, 48, 52, 58, 60, 94, 107, 109, 110, 119, 131 and 155

Suitable reactive dyes for 5 color jet injection inks include:

• Reagent Yellow I.C. 1, 2, 3, 14, 15, 17, 37, 42, 76, 95, 168 and 175

• Reactive Red I.C. 2, 6, 11, 21, 22, 23, 24, 33, 45, 111, 112, 114, 180, 218, 266, 228 and 235

• Reactive Blue I.C. 7, 14, 15, 18, 19, 21, 25, 38, 49, 72, 77, 176, 203, 220, 10 230 and 235

• Orange Reagent I.C. 5, 12, 13, 35 and 95

• Reactive Brown I.C. 7, 11, 33, 37 and 46

• Reactive green I.C. 8 and 19

• Violet reactive I.C. 2, 4, 6, 8, 21, 22 and 25 15

• Reactive black I.C. 5, 8, 31 and 39

Basic dyes suitable for color jet injection inks include:

• Basic Yellow I.C. 11, 14, 21 and 32

• Basic Red I.C. 1, 2, 9, 12 and 13 20

• Basic Violet I.C. 3, 7 and 14

• Basic Blue I.C. 3, 9, 24 and 25

If the color inkjet ink contains water, the dyes may manifest only the ideal color in an appropriate range of pH value. Therefore, the inkjet ink further comprises preferably a pH adjuster.

Suitable pH adjusters include NaOH, KOH, Net3, HCI, HNO3, H2SO4 and (poly) alkanolamines such as triethanolamine and 2-amino-2-methyl-1-propanol. Preferred pH adjusters are NaOH and H2SO4.

The dyes are used in the color inkjet ink in an amount of 0.1 to 30% by weight, preferably 1 to 20% by weight based on the total weight of the inkjet ink.

In a specific embodiment, the dye is a fluorescent dye used to introduce safety features. Suitable examples of a fluorescent dye include Tinopal ™ grades such as Tinopal ™ SFD, Uvitex ™ grades such as Uvitex ™ NFW and Uvitex ™ OB, all available from CIBA SPECIALTY CHEMICALS; Leukophor ™ qualities from CLARIANT and Blancophor ™ qualities such as Blancophor ™ REU and Blancophor ™ BSU from BAYER.

Dispersants

The dispersant is preferably a polymeric dispersant. Typical polymeric dispersants are copolymers of two monomers but may contain three, four, five or even more monomers. The properties of polymeric dispersants depend on both the nature of the monomer and its distribution in the polymer. Suitable copolymer dispersants have the following polymer compositions:

• statistically polymerized monomers (for example monomers A and B polymerized in ABBAABAB); 10

• alternatively polymerized monomers (eg monomers A and B polymerized in ABABABAB);

• polymerized gradient (tapered) monomers (for example, A and B monomers polymerized in AAABAABBABBB);

• block copolymers (for example monomers A and B polymerized in 15 AAAAABBBBBB) in which the block length of each of the blocks (2, 3, 4, 5 or even more) is important for dispersant dispersibility polymeric;

• graft copolymers (graft copolymers consisting of a polymeric main chain with polymeric side chains attached to the main chain); Y

• mixed forms of these polymers, for example block gradient copolymers.

Polymeric dispersants can have different polymeric architecture including linear, comb / branched, star, dendritic (which includes dendrimers and hyperbranched polymers). A general review of the polymer architecture is given in ODIAN, George, Principies of Polymerization, 4th edition, Wiley-Intersciencie, 2004, p. 1-18.

Comb / branched polymers have lateral branches of attached monomer molecules protruding from various central branching points along the main polymer chain (at least 3 branching points).

Star polymers are branched polymers in which three or more same or different linear homopolymers or copolymers are attached to a single core. 35

Dendritic polymers comprise the class of dendrimers and hyperbranched polymers. In dendrimers, with well-defined mono-dispersed structures, all branching points (multistage synthesis) are used, while hyperbranched polymers have a plurality of branching points and multifunctional branching that lead to additional branching with polymer growth. (one stage polymerization process).

Suitable polymeric dispersants can be prepared through addition or condensation polymerizations. Polymerization methods include those described by ODIAN, George, Principles of Polymerization, 4th edition, Wiley-Intersciencie, 2004, p. 39-606.

Addition polymerization methods include free radical polymerization (FRP) and controlled polymerization technique. Suitable controlled radical polymerization methods include:

• RAFT: chain transfer by reversible addition-fragmentation;

• ATRP: radical polymerization with atom transfer

• MADIX: chain transfer process by reversible addition-fragmentation, using an active xanthate transfer; fifteen

• Catalytic chain transfer (for example using cobalt complexes);

• Nitroxide-mediated polymerizations (for example TEMPO)

Other suitable control polymerization methods include:

• GTP: group transfer polymerization; twenty

• Live cationic (ring opening) polymerizations;

• Ring opening polymerization by anionic coordination-insertion; Y

• Live anionic (ring opening) polymerization.

Reversible addition-fragmentation transfer (RAFT): controlled polymerization takes place through rapid chain transfer between growing polymer radicals and inactive polymer chains. A review article on the RAFT synthesis of dispersants with different polymer geometry is given in QUINN J.F. et al., Facile Synthesis of comb, star, and graft polymers via reversible addition-fragmentation chain 30 transfer (RAFT) polymerization, Journal of Polymer Science, Part A: Polymer Chemistry, Vol. 40, 2956-2966, 2002.

Group Transfer Polymerization (GTP): The GTP method used for the synthesis of AB block copolymers is described in SPINELLI, Harry J, GTP and its use in water based pigment dispersants and emulsion 35 stabilisers, Proc. of 20th Int. Conf. Org. Coat Sci. Technol., New Platz, N.Y., State Univ. N.Y., Inst. Mater. Sci. P. 511-518.

The synthesis of dendritic polymers is described in the literature. The synthesis of dendrimers in NEWCOME, G.R., et al. Dendritic Molecules: Concepts, Synthesis, Perspectives. VCH: WEINHEIM, 2001. Hyperbranching polymerization is described in BURCHARD, W. Solution properties of branched macromolecules. Advances in Polymer Science. 1999, vol. 143, No. II, p. 113-194. Hyperbranched materials can be obtained by polyfunctional polycondensation as described by FLORY, P.J. Molecular size distribution in three-dimensional polymers. SAW. Branched polymer containing A-R-Bf-1-type units. Journal of the American Chemical Society. 1952, vol. 74, p. 2718-1723.

Live cationic polymerizations are used, for example, for the synthesis of polyvinyl ethers as described in WO 2005/012444 (CANON), US 20050197424 (CANON) and US 20050176846 (CANON). Ring opening polymerization by anionic coordination is used for example for the synthesis of lactose-based polyesters. The live anionic ring opening polymerization is used for example for the synthesis of polyethylene oxide macromonomers.

Free Radical Polymerization (FRP) takes place through a chain mechanism, which basically consists of four different types of reactions that involve free radicals: (1) generation of radicals from non-radical species (initiation), (2) addition of radicals to a substituted alkene (propagation), (3) atoms transfer reactions and atom abstraction (chain transfer and disproportionation termination) and (4) radical-radical recombination reactions (termination by combination).

Polymeric dispersants having several of the above polymeric compositions are described in US 6022908 (HP), US 5302197 (DU PONT) and US 6528557 (XEROX).

Suitable statistical copolymer dispersants are described in US 5648405 (DU PONT), US 6245832 (FUJI XEROX), US 6262207 (3M), US 20050004262 (KAO) and US 6852777 (KAO). 30

Suitable alternative copolymer dispersants are described in US 20030017271 (AKZO NOBEL).

Suitable block copolymer dispersants have been described in numerous patents, especially block copolymer dispersants containing hydrophobic and hydrophilic blocks. For example, US 355859113 (DU PONT) describes AB block copolymers, US 6413306 (DU PONT) describes ABC block copolymers.

Suitable copolymeric graft dispersants are described in CA 2157361 (DU PONT) (hydrophobic polymer main chain and hydrophilic side chains); Other graft copolymer dispersants are described in US 6652634 (LEXMARK), US 6521715 (DU PONT).

Suitable branched copolymer dispersants are described in US 6005023 (DU PONT), US 6031019 (KAO), US 6127453 (KODAK).

Suitable dendritic copolymer dispersants are described, for example, in US 6518370 (3M), US 6258896 (3M), US 2004102541 (LEXMARK), US 6649138 (QUANTUM DOT), US 2002256230 10 (BASF), EP 1351759 A ( EFKA ADDITIVES) and EP 1295919 A (KODAK).

Suitable designs of polymeric dispersants for jet injection inks are described in SPINELLI, Harry J., Polymeric Dispersants in Inkjet technology, Advanced Materials, 1998, Vol. 10, No. 15, p. 1215-1218. fifteen

The monomers and / or oligomers used to prepare the polymeric dispersant can be any monomer and / or oligomer found in Polymer Handbook Vol. 1 + 2, 4th edition, edited by J. BRANDRUP et al., Wiley-lnterscience, 1999.

Polymers useful as pigment dispersants include naturally occurring polymers and specific examples thereof include: proteins, such as gluten, gelatin, casein and albumin; gums of natural origin, such as gum arabic and tragacanth; glycosides such as saponin; alginic acid and alginic acid derivatives, such as propylene glycol alginate; and cellulose derivatives, such as methyl cellulose, carboxymethyl cellulose and ethylhydroxy cellulose; wool, silk and synthetic polymers.

Suitable examples of monomers for synthesizing polymeric dispersants include: acrylic acid, metracrylic acid, maleic acid (or salts thereof), maleic anhydride, alkyl (meth) acrylates (linear, branched and cycloalkyl) such as methyl (meth) acrylate, n-butyl (meth) acrylate, tert-30 butyl (meth) acrylate, cyclohexyl (meth) acrylate and 2-ethylhexyl (meth) acrylate; aryl (meth) acrylates such as benzyl (meth) acrylate and phenyl (meth) acrylate; hydroxyalkyl (meth) acrylates such as hydroxyethyl (meth) acrylate and hydroxypropyl (meth) acrylate; (meth) acrylates with other types of functionalities (for example substituted with oxiranes, amino, fluoro, polyethylene oxide, phosphate) such as glycidyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, trifluoroethyl acrylate, methoxypolyethylene glycol (meth) acrylate and tripropylene glycol (meth) acrylate phosphate; allyl derivatives such as allyl glycidyl ether; styrenes such as styrene, 4-methylstyrene, 4-hydroxystyrene, 4-aceto-styrene and styrene sulfonic acid; (meth) acrylonitrile; (meth) acrylamides (including N-mono and N, N-disubstituted) such as N-benzyl (meth) acrylamide; maleimides such as N-phenyl maleimide; vinyl derivatives such as vinyl alcohol, vinylprolactam, vinyl pyrrolidone, vinylimidazole, vinyl naphthalene and vinyl halides; vinyl ethers such as vinyl methyl ether; vinyl esters of carboxylic acids such as vinyl acetate, vinyl butyrate and vinyl benzoate. Typical condensation type polymers include polyurethanes, polyamides, polycarbonates, polyethers, polyureas, polyimines, polyimides, polyketones, polyester, polysiloxane, phenolformaldehyde, urea formaldehyde, melamine formaldehyde, polysulfide, polyacetal or combinations thereof.

Suitable copolymer dispersants are acrylic / acrylonitrile acid copolymer, vinyl acetate / acrylic ester copolymer, acrylic acid / acrylic ester copolymer, styrene / acrylic acid copolymer, styrene / methacrylic acid copolymer, styrene / methacrylic acid copolymer / acrylic ester, styrene / α-methylstyrene / acrylic acid copolymer, styrene / α-methylstyrene / acrylic acid copolymer / acrylic ester, styrene / maleic acid copolymer, styrene / maleic anhydride copolymer, vinylnaphthalene / acrylic acid copolymer, acrylic vinylnaphthalene / maleic acid copolymer, vinyl acetate / ethylene copolymer, vinyl acetate / fatty acid / ethylene copolymer, vinyl acetate / maleic ester copolymer, vinyl acetate / crotonic acid copolymer, vinyl acetate / acrylic acid copolymer.

Suitable chemicals of copolymer dispersants also include:

• Copolymers that are the product of a condensation process of poly (ethylene iminia) with a carboxylic acid terminated in polyester (prepared by addition polymerization); Y

• Copolymers that are the product of a reaction of a multifunctional isocyanate with:

- a monosubstituted compound with a group that is capable of reacting with an isocyanate, for example polyester;

- a compound containing two groups capable of reacting with an isocyanate (crosslinker); I

- a compound with at least one nitrogen in the basic ring and a group that is capable of reacting with an isocyanate group. 35

A detailed list of suitable polymeric dispersants is described in MC CUTCHEON, Functional Materials, North American Edition, Glen Rock, N.J .: Manufacturing Confectioner Publishing Co., 1990, p. 110-129.

Suitable pigment stabilizers are also described in DE 19636382 (BAYER), US 5720802 (XEROX), US 5713993 (DU PONT), WO 96/12772 (XAAR) and US 5085689 (BASF).

A polymeric dispersant or a mixture of two or more polymeric dispersants may be present to improve the stability of the dispersion further. Sometimes surfactants can also be used as pigment dispersants, therefore a combination of a polymeric dispersant with a surfactant is also possible.

The polymeric dispersant can be nonionic, anionic or cationic by nature; salts of ionic dispersants may also be used.

The polymeric dispersant preferably has a degree of DP polymerization between 5 and 1000, more preferably between 10 and 500 and most preferably between 10 and 100.

The polymeric dispersant preferably has an average molecular weight value PM between 500 and 30000, more preferably between 1500 and 150000.

The polymeric dispersant preferably has an average molecular weight PM value of less than 100,000, more preferably less than 50,000 and most preferably less than 30,000.

The polymeric dispersant preferably has a polymeric DP dispersibility 20 less than 2, more preferably less than 1.75 and most preferably less than 1.5.

The commercially available examples of polymeric dispersants are as follows:

• DISPERBYK ™ dispersants available from BYK CHEMIE GMBH; 25

• SOLSPERSE ™ dispersants available in NOVEON;

• TEGO ™ DISPERS ™ dispersants from DEGUSSA;

• EDAPLAN ™ dispersants from MÜNZING CHEMIE;

• ETHACRYL ™ dispersants from LYONDELL;

• ISP GANEX ™ dispersants; 30

• DISPEX ™ and EFKA ™ dispersants from CIBA SPECIALTY CHEMICALS INC;

• DISPONER ™ DEUCHEM dispersants; Y

• JONCRYL ™ dispersants from JOHNSON POLYMER.

Particularly preferred polymeric dispersants include 35 Solsperse ™ dispersants from NOVEON, Efka ™ dispersants from CIBA SPECIALTY CHEMICALS INC and Disperbyk ™ dispersants from BYK CHEMIE GMBH.

Particularly preferred dispersants for UV curable pigmented dispersions are Solsperse ™ 32000, 35000 and 39000 dispersants from NOVEON.

Particularly preferred dispersants for oil-based pigmented dispersions are Solsperse ™ 11000, 11200, 13940, 16000, 5 17000 and 19000 from NOVEON.

The polymeric dispersant is preferably used in an amount of 2 to 600% by weight, more preferably 5 to 200% by weight based on the weight of the pigment.

Synergic Dispersion 10

Synergists of dispersion normally consist of an anionic part and a cationic part. The anionic part of the synergic dispersion shows a certain molecular similarity with the color pigment and the cationic part of the synergic dispersion consists of one or more protons and / or cations to compensate for the charge of the anionic part of the synergic dispersion.

The synergist is preferably added in an amount less than the polymer dispersant or dispersants. The proportion of polymer dispersion / synergic dispersion depends on the pigment and should be determined experimentally. Typically, the percentage by weight of polymeric dispersant 20 /% by weight of synergistic dispersion is selected from 2: 1 to 100: 1, preferably between 2: 1 and 20: 1.

Suitable dispersion synergists that are commercially available include Solsperse ™ 5000 and Solsperse ™ 22000 from NOVEON.

Particularly preferred pigments for the magenta ink used are a diketopyrol-pyrrole pigment or a quinacridone pigment. Suitable dispersion synergists include those described in EP 1790698 A (AGFA GRAPHICS) and EP 1790695 A (AGFA GRAPHICS).

In the dispersion of the Blue Pigment I.C. 15: 3, the use of a synergistic dispersion of Cu-phthalocyanine, for example, Solsperse ™ from NOVEON, is preferred. Suitable dispersion synergists for yellow jet injection inks include those described in EP 1790697 A (AGFA GRAPHICS).

Means of dispersion 35

In one embodiment the dispersion medium consists of organic solvent or solvents. Suitable organic solvents include alcohols, ketones, esters, ethers, glycols and polyglycols and derivatives thereof, lactones, N-containing solvents such as amides. Preferably, mixtures of one or more of these solvents are used.

Examples of suitable alcohols include methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, heptyl alcohol, octyl alcohol, cyclohexyl alcohol, benzyl alcohol, phenylethyl alcohol, phenylpropyl alcohol, furfuryl alcohol, anise alcohol and fluoroalcohols.

Examples of suitable ketones include acetone, methyl ethyl ketone, methyl n-propyl ketone, methyl isopropyl ketone, methyl n-butyl ketone, methyl isobutyl ketone, methyl n-amyl ketone, methyl isoamil ketone, diethyl ketone, ethyl n-propyl ketone, ethyl 10 isopropyl ketone, ethyl n-butyl ketone, ethyl isobutyl ketone, di-n-propyl ketone, diisobutyl ketone, cyclohexanone, methylcyclohexanone and isophorone, 2,4-pentanedione and hexafluoroacetone.

Examples of suitable esters include methyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, hexyl acetate, octyl acetate, benzyl acetate, phenoxyethyl acetate, ethylphenyl acetate, methyl lactate, ethyl lactate, propyl lactate, butyl lactate; methyl propionate, ethyl propionate, benzyl propionate, ethylene carbonate, propylene carbonate, amyl acetate, ethyl benzoate, butyl benzoate, butyl laurate, isopropyl myristate, isopropyl palmirate, triethyl phosphate, phosphate of tributyl, diethyl phthalate, dibutyl phthalate, diethyl malonate, dipropyl malonate, diethyl succinate, dibutyl succinate, diethyl glutarate, diethyl adipate, dibutyl adipate and diethyl sebacate.

Examples of suitable ethers include butyl phenyl ether, benzyl ethyl ether, hexyl ether, diethyl ether, dipropyl ether, tetrahydrofuran and dioxane.

Examples of suitable glycols and polyglycols include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol and tripopylene glycol.

Examples of suitable glycol and polyglycol derivatives include ethers, such as akylene glycol mono alkyl ethers, akylene glycol dialkyl ethers, polyalkylene glycol monoalkyl ethers, polyalkylene glycol dialkyl ethers and esters of the above glycol ethers such as acetate and propionate esters, in case of dialkyl ethers Only one ether function (resulting in mixed ether / ester) or both ether functions can be esterified (resulting in dialkyl ester). 35

Examples of suitable alkylene glycol mono alkyl ethers include ethylene glycol mono methyl ether, ethylene glycol monoethyl ether, ethylene glycol mono propyl ether, ethylene glycol mono butyl ether, ethylene glycol mono hexyl ether, ethylene glycol mono 2-ethyl hexyl ether, ethylene glycol mono phenyl ether, ethylene glycol mono phenyl ether, ether, propylene glycol mono ethyl ether, propylene glycol mono-n-propyl ether, propylene glycol mono-n-butyl ether, propylene glycol mono-iso-butyl ether, propylene glycol mono-t-butyl ether and propylene glycol mono phenyl ether.

Examples of suitable alkylene glycol dialkyl ethers include ethylene glycol 5 dimethyl ether, ethylene glycol diethyl ether, ethylene glycol methyl ethyl ether, ethylene glycol dibutyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether and propylene glycol dibutyl ether.

Examples of suitable polyalkylene glycol mono alkyl ethers include diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol mono-n-10 propyl ether, diethylene glycol mono-n-butyl ether, diethylene glycol mono-hexyl ether, triethylene glycol mono methyl, triethylene glycol monoethylene ether mono butyl ether, dipropylene mono methyl ether, dipropylene glycol mono ethyl ether, dipropylene glycol n-propyl ether, dipropylene glycol mono-n-butyl ether, dipropylene mono-t-butyl ether, tripropylene glycol mono methyl ether, tripropylene glycol mono ether, tripropylene glycol n-propyl ether and tripropylene glycol mono n-butyl ether.

Examples of suitable polyalkylene glycol dialkyl ethers include diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, diethylene glycol diethyl ether, triethylene glycol diethyl ether, tetraethylene glycol diethyl ether, diethylene glycol methyl ethyl ether, methyl ethyl ether, methyl ethyl ether, methyl ethyl ether, methyl ethyl ether, methyl ethyl ether, methyl ethyl ether, methyl ethyl ether, methyl ethyl ether, methyl ethyl ether, methyl ethyl ether, methyl ethyl ether, methyl ethyl ether, methyl ethyl ether, methyl ethyl ether, methyl ethyl ether, methyl ethyl ether n-propyl ether, diethylene glycol di-isopropyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, dipropylene di-n-propyl ether, dipropylene di-t-butyl ether, tripropylene glycol dimethyl ether and tripropylene glycol diethyl ether.

Examples of suitable glycol esters include ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol 25 monopropyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, propylene glycol acetate, propylene glycol acetate propylene glycol monoethyl ether acetate, dipropylene glycol monomethyl ether acetate and propylene glycol monomethyl ether propionate.

Preferred solvents for use in pigment dispersions and 30 jet injection inks are one or more polyalkylene glycol dialkyl ethers represented by the formula (PAG)

Formula (PAG)

in which,

each of R1 and R2 is independently selected from an alkyl group having 1 to 4 carbon atoms;

Y represents an ethylene group and / or a propylene group; in which

n is an integer selected from 4 to 20. Preferably, a mixture of two or more polyalkylene glycol dialkyl ethers represented by the formula (PAG).

The alkyl groups R1 and R2 of the polyalkylene glycol dialkyl ethers according to the Formula (PAG) preferably represent methyl and / or ethyl. More preferably, the alkyl groups R1 and R2 are methyl groups.

In a preferred embodiment the polyalkylene glycol dialkyl ethers according to the Formula (PAG) are polyethylene glycol dialkyl ethers.

In another preferred embodiment, a mixture of 2, 3, 4 or more polyalkylene glycol dialkyl ethers, more preferably polyethylene glycol 10 dialkyl ethers, is present in the pigment dispersion or the inkjet ink.

Suitable mixtures of polyalkylene glycol dialkyl ethers for pigment dispersions include mixtures of polyethylene glycol dimethyl ethers having a molecular weight of at least 200, such as Polyglycol DME 15 200 ™, Polyglycol DME 250 ™ and Polyglycol DME 500 ™ from CLARIANT. The polyalkylene glycol dialkyl ethers used in non-aqueous jet injection inks preferably have an average molecular weight between 200 and 800, and more preferably no polyalkylene glycol dialkyl ethers with a molecular weight of more than 800 are present. The mixture of polyalkylene glycol dialkyl ethers is preferably a mixture. homogeneous liquid at room temperature.

Suitable commercially available ether glycol solvents include Cellosolve ™ solvents and Carbitol ™ solvents from UNION CARBIDE, Ektasolve ™ solvents from EASTMAN, Dowanol ™ solvents from DOW, Oxitoll ™ solvents, Dioxitoll ™ solvents, Proxitoll ™ solvents and 25 Diprox solvent solvents from SHELL CHEMICAL and Arcosolv ™ solvents from LYONDELL.

Lactones are compounds that have a ring structure formed by ester bonds and can be of the γ-lactone (5-member ring structure), δ-lactone (6-member ring structure) or ε-30 lactone (structure 7-member ring). Suitable examples of lactones include γ-butyrolactone, γ-valerolactone, γ-hexalactone, γ-heptalactone, γ-octalactone, γ-nonalactone, γ-decalactone, γ-undecalactone, δ-valerolactone, δ-hexalactone, δ δ-octalactone, δ-nonalactone, δ-decalactone, δ-undecalactone and ε-caprolactone. 35

Suitable examples of organic solvents containing N include 2-pyrrolidone, N-methylpyrrolidone, N-ethyl-2-pyrrolidone, N-octyl-2-pyrrolidone, N-dodecyl-2-pyrrolidone, N, N-dimethylacetamide, N, N -dimethylformamide, acetonitrile and N, N-dimethyldodecanamide.

In another embodiment, the dispersion medium comprises oily types of liquids alone or in combination with organic solvent or solvents. Suitable organic solvents include alcohols, ketones, esters, ethers, glycols and polyglycols and derivatives thereof, lactones, N-containing solvents such as amides, higher fatty acid ester and mixtures of one or more of the solvents as has been described above for solvent based dispersion media.

The amount of polar solvent is preferably less than the amount of oil. The organic solvent preferably has a high boiling point, preferably above 200 ° C. Examples of suitable combinations are described in GB 2303376 (FUJITSU ISOTEC) especially the use of oleyl alcohol and EP 1157070 A (MARCONI DATA SYSTEMS) for the combination of oil and volatile organic solvent. fifteen

Suitable oils include saturated hydrocarbons and unsaturated hydrocarbons, aromatic oils, paraffinic oils, extracted paraffinic oils, naphthenic oils, extracted naphthenic oils, light or heavy hydrotreated oils, vegetable oils, white oils, petroleum naphtha oils, halogen substituted hydrocarbons, silicones and 20 derivatives and mixtures thereof.

The hydrocarbons can be selected from straight chain or branched chain aliphatic hydrocarbons, alicyclic hydrocarbons and aromatic hydrocarbons. Examples of hydrocarbons are saturated hydrocarbons such as n-hexane, isohexane, n-nonano, isononane, dodecane and isododecane; Unsaturated hydrocarbons such as 1-hexene, 1-heptene and 1-octene; saturated cyclic hydrocarbons such as cyclohexane, cycloheptane, cyclooctane, cyclodecane and decalin; cyclic unsaturated hydrocarbons such as cyclohexene, cycloheptene, cyclooctene, 1,3,5,7-cyclooctatetraen; and cyclododecene; and aromatic hydrocarbons such as benzene, toluene, xylene, naphthalene, phenanthrene, anthracene and derivatives thereof. In the literature the expression paraffinic oil is normally used. Suitable paraffinic oils may be of the normal paraffin type (octane and higher alkanes), isoparaffins (isooctane and higher iso-alkanes) and cycloparaffins (higher cyclooctanes and cycloalkanes) and mixtures of paraffin oils. The term "liquid paraffin" is normally used to refer to a mixture comprising mainly three components of a normal paraffin, an isoparaffin and a monocyclic paraffin, which is obtained by highly refining a fraction of volatile lubrication oil through a bath of sulfuric acid or the like, as described in US 6730153 (SAKATA INX). Suitable hydrocarbons are also described as dearomatized petroleum distillates.

Suitable examples of halogenated hydrocarbons include methylene dichloride, chloroform, tetrachloromethane and methyl chloroform. Other suitable examples of halogen substituted hydrocarbons include perfluoroalkanes, inert fluids based on fluorine and fluorocarbon iodides.

Suitable examples of silicone oils include dialkyl polysiloxane (eg, hexamethyl disiloxane, tetramethyl disiloxane, octamethyl trisiloxane, 10 hexamethyl trisiloxane, heptamethyl trisiloxane, decamethyl tetrasiloxane, trifluoropropyl heptamethyl trisiloxane, diethyl tetramethyl cyclohexyl cyclohexyl cyclohexyl cyclohexyl cyclohexyl cyclohexyl cyclohexane , octamethyl cyclotetrasiloxane, tetramethyl cyclotetrasiloxane, tetra (trifluoropropyl) tetramethyl cyclotetrasiloxane) and methylphenyl silicone oil. fifteen

White oil is an expression used for white mineral oils, which are highly refined mineral oils that consist of saturated non-polar aliphatic and alicyclic hydrocarbons. White oils are hydrophobic, colorless, tasteless, odorless, and do not change color over time.

Vegetable oils include semi-dry oils such as soybean oil, cottonseed oil, sunflower oil, rapeseed oil, mustard oil, sesame oil and corn oil; un dried oils such as olive oil, peanut oil and tsubaki oil; and dry oils such as flaxseed oil and safflower oil, in which these vegetable oils can be used alone or as a mixture thereof. 25

Examples of other suitable oils include petroleum oils, un dried oils and semi-dry oils.

Suitable commercially available oils include types of aliphatic hydrocarbons such as the Isopar ™ range (isoparaffins) and the Varsol / Naphtha range of EXXON CHEMICAL, the Soltrol ™ range and the 30 CHEVRON PHILLIPS CHEMICAL hydrocarbons and the Shellsol ™ range of SHELL CHEMICALS.

Suitable commercially available normal paraffins include the Norpar ™ range of EXXON MOBIL CHEMICAL.

Suitable commercially available naphthenic hydrocarbons 35 include the Nappar ™ range of EXXON MOBIL CHEMICAL.

Suitable commercially available dearomatized petroleum distillates include the Exxsol ™ types of EXXON MOBIL CHEMICAL.

Suitable commercially available fluoro-substituted hydrocarbons include fluorocarbons from DAIKIN INDUSTRIES LTD, Chemical Division.

Suitable commercially available silicone oils include the silicone fluid ranges of SHIN-ETSU CHEMICAL, Silicone 5 Division.

Suitable commercially available white oils include Witco ™ white oils from CROMPTON CORPORATION.

If the non-aqueous pigment dispersion is a curable pigment dispersion, the dispersion medium comprises one or more monomers and / or 10 oligomers to obtain a liquid dispersion medium. Sometimes, it may be advantageous to add a small amount of an organic solvent to improve dissolution of the dispersant. The organic solvent content should be less than 20% by weight based on the total weight of the jet ink. In other cases, it may be advantageous to add a small amount of water, for example, to improve the spread of the inkjet ink on a hydrophilic surface, but preferably the inkjet ink does not contain water.

Preferred organic solvents include alcohols, aromatic hydrocarbons, ketones, esters, aliphatic hydrocarbons, higher fatty acids, carbons, cellosolves, higher fatty acid esters. Suitable alcohols include methanol, ethanol, propranol and 1-butanol, 1-pentanol, 2-butanol, t-butanol. Suitable aromatic hydrocarbons include toluene and xylene. Suitable ketones include methyl ethyl ketone, methyl isobutyl ketone, 2,4-pentanedione and hexafluoroacetone. Glycol, glycoethers, N-methylpyrrolidone, N, N-dimethylacetamide, N, N, dimethylformamide can also be used.

In the case of a curable jet ink, the dispersion medium preferably consists of monomers and / or oligomers.

Monomers and oligomers 30

Any monomer or oligomer can be used as a curable compound for the curable inkjet ink. A combination of monomers, oligomers and / or prepolymers can also be used. The monomers, oligomers and / or prepolymers can have different degrees of functionality and a mixture can be used that includes combinations of mono-35, di-, tri-monomers and higher functionalities, oligomers and / or prepolymers. The viscosity of the inkjet ink can be adjusted by varying the ratio between monomers and oligomers.

Any conventional radical polymerization method, photo-curing system using photo acid or base photo generators, or alternating photo induction copolymerization can be used. In general, radical polymerization and cationic polymerization are preferred and alternating photo induction copolymerization which does not require initiator can also be employed. In addition, a hybrid system of combinations of these systems is also effective.

Cationic polymerization is superior in efficiency due to the absence of inhibition of oxygen polymerization, however it is expensive and slow, especially in conditions of high relative humidity. If cationic polymerization is used, it is preferred to use an epoxy compound together with an oxetane compound to increase the polymerization rate. Radical polymerization is the preferred polymerization process.

Any polymerizable compound commonly known in the art can be used. Particularly preferred for use as a radiation curable compound in the radiation curable inkjet ink are monofunctional and / or plurifunctional acrylate monomers, oligomers or prepolymers, such as isoamyl acrylate, stearyl acrylate, lauryl acrylate , octyl acrylate, decyl acrylate, isoamylstyl acrylate, isostearyl acrylate, 2-ethylhexyl diglycol acrylate, 2-hydroxybutyl acrylate, 2-20 acryloxyxyethylhexahydrophthalic acid, butoxy ethyl acrylate acrylate, acrylate acrylate acrylate, acrylate acrylate acrylate acrylate acrylate of methoxypolyethylene glycol, methoxypropylene glycol acrylate, phenoxyethyl acrylate, tetrahydrofurfuryl acrylate, isobornyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxy-3-acryloxy, ethoxypropyl acrylate ) vinyl ether acrylate, 2-acryloxyxyethyl succinic acid, 2-acryloxyethylphthalic acid, a 2-acryloxyethyl-2-hydroxyethyl-phthalic acid, lactone-modified flexible acrylate and t-butylcyclohexyl acrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, diapropylene glycol diacrylene glycol diacrylate, 30-diarylene glycol diacrylate, polypropylene glycol diarylate 1,4-butanediol, 1,6-hexanediol diacrylate, 1,9-nonanodiol diacrylate, neopentyl glycol diacrylate, dimethyloltricyclodecane diacrylate, bisphenol A OE adduct diacrylate (ethylene oxide), bisphenol A OP adduct diacrylate (propylene oxide), neopentyl glycol hydroxypivalate diacrylate, propoxylated neopentyl glycol diacrylate, alkoxylated dimethyloltricyclodecane diacrylate and polytetramethylene glycol diacrylate, trimethylolpropane triacrylate triacrylate triacrylate, modified trimethylpropylene triacrylate triacrylate , pentaerythritol triacrylate, tetraac pentaerythritol rilate, pentaerythritolotroxy tetraacrylate, dipentaerythritol hexaacrylate, dithrimethylolpropane tetraacrylate, glycerinpropoxy tetraacrylate and dipentaerythritol hexaacrylate modified with caprolactam or such an N-vinyl formate or as N-vinyl formate or as N-vinylidem, such as N-vinyl formate or N-vinylidem, such as N-vinyl acetate or N-vinyl formamide; or acrylamide or a substituted acrylamide, such as acryloylmorpholine.

Other suitable monofunctional acrylates include caprolactone acrylate, cyclic trimethylolpropane acrylate, ethoxylated nonyl phenol acrylate, isodecyl acrylate, isooctyl acrylate, octildecyl acrylate, alkoxylated alkoxylated acrylate dimethyl acrylate acrylate acrylate.

Other suitable difunctional acrylates include alkoxylated cyclohexanone dimethyl diacrylate, alkoxylated hexanediol diacrylate, dioxanglycol diacrylate, dioxanglycol diacrylate, cyclohexanone dimethyl diacrylate, diethylene glycol diacrylate and neopentyl glycol diacrylate. fifteen

Other suitable trifunctional acrylates include propoxylated glycerin triacrylate and propoxylated trimethylolpropane triacrylate.

Other higher functional acrylates include di-trimethylolpropane tetraacrylate, dipentaerythritol pentaacrylate, ethoxylated pentaerythritol tetraacrylate, methoxylated glycol acrylates and acrylate esters. twenty

In addition, methacrylates that correspond to the acrylates mentioned above can be used with these acrylates. Of the methacrylates, methoxy polyethylene glycol methacrylate, methoxytriethylene glycol methacrylate, hydroxyethyl methacrylate, phenoxyethyl methacrylate, clicklohexyl methacrylate, tetraethylene glycol dimethacrylate and dimethylacrylate due to a relatively high surface adhesion receive a higher sensitivity.

In addition, jet injection inks may also contain polymerizable oligomers. Examples of these polymerizable oligomers include epoxy acrylates, aliphatic urethane acrylates, aromatic uteran acrylates, polyester acrylates and straight chain acrylic oligomers.

Suitable examples of styrene compounds are styrene, p-methylstyrene, p-methoxystyrene, β-methylstyrene, p-methyl-β-methylstyrene, α-methylstyrene and p-methoxy-β-methylstyrene.

Suitable examples of vinylnaphthalene compounds are 1-35 vinylnaphthalene, α-methyl-1-vinylnaphthalene, β-methyl-1-vinylnaphthalene, 4-methyl-1-vinylnaphthalene, and 4-methoxy-1-vinylnaphthalene.

Suitable examples of N-vinyl compounds are N-vinylcarbazole, N-vinylpyrrolidone, N-vinylindole, N-vinylpyrrole, N-vinylphenothiazine, N-vinyl acetoanilide, N-vinyl ethylacetoamide, N-vinyl succinimide, N-vinylphthalimide, N-vinylcaprolama N -vinylimidazole.

The cationically polymerizable compound of the jet ink may be one or more monomers, one or more oligomers or a combination thereof.

Suitable examples of cationically curable compounds can be found in Advances in Polymer Science, 62, pages 1 to 47 (1984) by J. V. Crivello.

The cationic curable compound may contain at least one olefin, thioether, acetal, thioxane, tiethane, aziridine, N-, O-, S- or P-heterocycle, aldehyde, lactam or cyclic ester group.

Examples of cationic polymerizable compounds include monomers and / or epoxides of oligomers, vinyl ethers, styrenes, oxetanes, oxazolines, vinyl naphthalenes, heterocyclic N-vinyl compounds, tetrahydrofurfuryl compounds.

The cationically polymerizable monomer can be mono-, di- or multifunctional or a mixture thereof.

Suitable cationic curable compounds having at least one epoxy group are indicated in the "Handbook of Epoxy Resins" by Lee and Neville, 20 McGraw Hill Book Company, New York (1967) and in "Epoxy Resin Technology" by PF Bruins, John Wiley and Sons New York (1968).

Examples of cationic curable compounds having at least one epoxy group include 1,4-butanediol diglycidyl ether, 3- (bis (glycidyloxymethyl) methoxy) -1,2-propanediol, limonene oxide, 2-biphenyl glycidyl ether, 3-carboxylate , 4-25 epoxycyclohexylmethyl-3 ', 4'-epoxycyclohexane, epoxides based on epichlorohydrin-bisphenol S, epoxidized styrenes and more epoxies based on epichlorohydrin-bisphenol F and A and epoxidized novolaks.

Suitable epoxy compounds comprising at least two epoxy groups in the molecule are polycyclic acid polyglycidyl ester, polyglycidyl ether of polyol, polyglycidyl ether of polyoxyalkylene glycol, polyglycidyl ester of aromatic polyol, polyglycidyl ether of aromatic polyol, compound urethane and polyepoxy polybutadiene.

Examples of cycloaliphatic bisepoxides include copolymers of epoxides and hydroxyl components such as glycols, polyols or vinyl ether, such as 3,4-epoxycyclohexylmethyl-3 ', 4'-epoxycyclohexylcarboxylate; bis (3,4-epoxycyclohexylmethyl) adipate; limonene bisepoxide; diglycidyl ester of hexahydrophthalic acid.

 Examples of vinyl ethers having at least one vinyl ether group include ethyl vinyl ether, n-butyl vinyl ether, isobutyl vinyl ether, octadecyl vinyl ether, cyclohexyl vinyl ether, butanediol divinyl ether, hydroxy butyl vinyl ether, cyclohexane dimethyl monovinyl ether, phenyl vinyl ether, p-methylphenyl vinyl ether, p-methoxyphenyl vinyl ether, α-methylphenyl vinyl ether, β-methylisobutyl vinyl ether and β-5 chloroisobutyl vinyl ether, diethylene glycol divinyl ether, triethylene glycol divinyl ether, n-propyl vinyl ether vinyl ether, dodecyl vinyl ether, diethylene glycol monovinyl ether, cyclohexanedimethanol divinyl ether, 4- (vinyloxy) butyl benzoate, bis [4- (vinyl oxy) butyl] adipate, bis [4- (vinyl oxy) butyl] succinate, 4- ( vinyloxy methyl) cyclohexylmethyl benzoate, bis [4- (vinyloxy) butyl] isophthalate, bis [4- (vinyloxymethyl) 10 cyclohexyl] methyl] glutarate, tris [4- (vinyloxy) butyl] trimellitate, 4- (vinyloxy) butyl steatite , bis [4- (vinyloxy) butyl] hexanediyl biscarbamate, bis [4- (vinyl xi) methyl] cyclohexyl] methyl] terephthalate, bis [4- (vinyloxy) methyl] cyclohexyl] methyl] isophthalate, bis [4- (vinyloxy) butyl] (4-methyl-1,3-phenylene) -biscarbamate, bis [ 4-vinyloxy) butyl] (methylene-4,1-phenylene) biscarbamate and 3-amino-15 1-propanol vinyl ether.

Suitable examples of oxetane compounds having at least one oxetane group include 3-ethyl-3-hydroloxymethyl-1-oxetane, the oligomeric mixture 1,4-bis [3-ethyl-3-oxetanyl methoxy) methyl] benzene, 3- ethyl-3-phenoxymethyl-oxetane, bis ([1-ethyl (3-oxetanyl)] methyl) ether, 3-ethyl-3- (2-ethylhexyloxy) methyl] oxetane, 3-ethyl - [(tri-20 ethoxysilyl propoxy ) methyl] oxetane and 3,3-dimethyl-2 (p-methoxy-phenyl) -oxetane.

A preferred class of monomers and oligomers that can be used in radiation and cationically curable compositions are vinyl ether acrylates such as those described in US 6310115 (AGFA), incorporated herein by reference. Particularly preferred compounds are 2- (2-vinyloxyethoxy) ethyl (meth) acrylate, more preferably the compound is 2- (2-vinyloxyethoxy) ethyl acrylate.

Initiators

The curable jet ink also preferably contains an initiator. The initiator typically initiates the polymerization reaction. The initiator may be a thermal initiator, but is preferably a photo-initiator. The photo-initiator requires less energy to activate than the monomers, oligomers and / or prepolymers to form the polymer. The photo-initiator suitable for use in curable jet injection inks may be a Norrish type I initiator, a Norrish 35 type II initiator or a photo-acid generator.

Suitable initiator or thermal initiators for use in curable jet ink include tert-amyl peroxybenzoate, 4,4-azobis (4-cyanovaleric acid), 1,1'-azobis (cyclohexanecarbonitrile), 2,2 ' -azobisisobutyronitrile (AIBN), benzoyl peroxide, 2,2-bis (tert-butylperoxy) butane, 1,1-bis (tert-butylperoxy) cyclohexane, 1,1-bis (tert-butylperoxy) cyclohexane, 2,5- bis (tert-butylperoxy) -2,5-dimethylhexane, 2,5-bis (tert-butylperoxy) -2,5-dimethyl-3-hexino, bis (1- (tert-butylperoxy) -1-methyl ethyl) benzene, 1,1-bis (tert-butylperoxy) -3,3,5-trimethylcyclohexane, tert-butyl hydroperoxide, tert-butyl peracetate, tert-butyl peroxide, tert-butyl peroxybenzoate, isopropyl carbonate tert-butylperoxy , cumene hydroperoxide, cyclohexanone peroxide, dicumyl peroxide, lauroyl peroxide, 2,4-pentanedione peroxide, paracetic acid and potassium persulfate. 10

The photo-initiator or photo-initiator system absorbs light and is responsible for the production of initiation species, such as free radicals and cations. Free radicals and cations are a high-energy species that induces the polymerization of monomers, oligomers and polymers and with polyfunctional monomers and oligomers, so they also induce crosslinking.

The irradiation with actinic radiation can be done in two stages by changing the wavelength or intensity. In such cases it is preferred to use two types of photo-initiator together.

A combination of different types of initiator can also be used, for example, a photo-initiator and a thermal initiator.

A preferred Norrish type I initiator is selected from the group consisting of benzoineethers, benzyl ketals, α, α-dialkoxyacetophenones, α-hydroxyalkylphenones, α-aminoalkylphenones, acylphosphine oxides, acylphosphine sulfides, α-haloketones, α-halosulfones and α-halophenylglioxalates. 25

A preferred Norrish type II initiator is selected from the group consisting of benzophenones, thioxanthones, 1,2-diketones and anthraquinones. A preferred co-initiator is selected from the group consisting of an aliphatic amine, an aromatic amine and a thiol. Tertiary amines, heterocyclic thiols and 4-dialkylamino-benzoic acid are particularly preferred as co-initiator.

Suitable photo-initiators are described in CRIVELLO, J.V., et al. VOLUME III: Photoinitiators for Free Radical Cationic, 2nd edition. Edited by BRADLEY, G. London, United Kingdom: John Wiley and Sons Ltd, 1998. p. 287-294. 35

Specific examples of photo-initiators may include, but are not limited to, the following compounds or combinations thereof: benzophenone and substituted benzophenones, 1-hydroxycyclohexyl phenyl ketone, thioxanthones such as isopropylthioxanthone, 2-hydroxy-2-methyl-1-phenylpropan -1-one, 2-benzyl-2-dimethylamino- (4-morpholinophenyl) butan-1-one, benzyl dimethylketal, bis (2,6-dimethylbenzoyl) -2,4, 4-trimethylpentylphosphine oxide, 2 oxide, 4,6-Trimethylbenzoyldiphenylphosphine, 2-methyl-1-] 4- (methylthio) phenyl] -2-morpholinopropan-1-one, 2,2-dimethoxy-1, 2-diphenylethane-1-one or 5,7-diiodo -3-butoxy-6-fluorone, diphenyldononium fluoride and triphenylsulfonium hexafluorophosphate.

Suitable commercially available photo-initiators include Irgacure ™ 184, Irgacure ™ 500, Irgacure ™ 907, Irgacure ™ 369, Irgacure ™ 1700, Irgacure ™ 651, Irgacure ™ 819, Irgacure ™ 1000, Irgacure ™ 1300, Irgacure ™ 1870, Darocur ™ 1173, Darocur ™ 2959, Darocur ™ 4265 and Darocur ™ ITX 10 available in CIBA SPECIALTY CHEMICALS, Lucerin TPO available in BASF AG, Esacure ™ KT046, Esacure ™ KIP150, Esacure ™ KT37 and Esacure ™ EDB available in LAMBERTI, H- Nu ™ 470 and H-Nu ™ 470X available at SPECTRA GROUP Ltd.

Suitable cationic photo initiators include compounds that form aprotic acids or Bronstead acids upon exposure to ultraviolet and / or visible light sufficient to initiate polymerization. In the photo-initiator used it can be a single compound, a mixture of two or more active compounds, or a combination of two or more different compounds, that is, co-initiators. Non-limiting examples of suitable cationic photo-initiators are aryldiazonium salts, diarylsodonium salts, triarylsulfonium salts, triarylselenonium salts and the like.

Suitable commercially available cationic photoinitiators include R-gen ™ 1130, R-gen ™ BF-1172, R-gen ™ 261, Chivacure ™ 1176 and Chivacure ™ 1190 from Chitec Technology Co., Ltd .; Irgacure ™ 250 from Ciba 25 Specialty Products; UV9387C and UV9380C from GE Silicones; Cyracure ™ UVI-6976 and UVI-6992 photoinitiator from The Dow Chemical Company; Omnicat ™ series from IGM Resins, including Omnicat 432 ™ (sulfonium type), Omnicat ™ 440 (iodonium type), Omnicat ™ 445 (iodonium type), Omnicat ™ 550 and Omnicat ™ 650 (polymeric type); Esacure ™ 1064, Esacure ™ 1187 and Esacure ™ 1188 from Lamberti 30 S.p.A .; Adeka Optomer ™ SP series of aromatic sulfonium cationic photo-initiators from Adeka Corporation, for example Adeka Optomer ™ SP-152; and OMPH076 from ABCR Gmbh Co. KG, a mixture of an aromatic sulfonium and aromatic thioether (available from B S Specialties BV under the trade name Sarcat KI85). 35

The curable inkjet ink may contain a photo-initiator system that contains one or more photo-initiators and one or more sensitizers that transfer energy to the photo-initiator or photo-initiators. Suitable sensitizers include photoreducible xanthene, fluorene, benzoxanthene, benzothioxanthene, thiazine, oxazine, coumarin, pironin, porphyrin, acridine, azo, diazo, cyanine, merocyanine, diarylmethyl, triarylmethyl, anthraquinone, phenylenediazole, naphthylenediazole, naphthylenediazole, naphthylenediazole, naphthylenediazole, naphthylenediazole, naphthylenediazole; , benzidine, rhodamine, indigo and / or indantrene dyes. The amount of the sensitizer is generally 0.01 to 15% by weight, preferably 0.05 to 5% by weight, in each case based on the total weight of the curable inkjet ink.

To increase the photosensitivity further, the curable jet ink may additionally contain co-initiators. For example, the combination of titanocenes and trichloromethyl-s-triazines, 10 titanocenes and ethers of ketoxime and acridines and trichloromethyl-s-triazines is known. An additional increase in sensitivity can be achieved by adding dibenzalacetone or amino acid derivatives. The amount of co-initiator or co-initiators is generally 0.01 to 20% by weight, preferably 0.05 to 10% by weight, in each case based on the total weight of the inkjet ink per jet. curable.

Suitable examples of co-initiators can be classified into 4 groups:

(1) tertiary aliphatic amines such as methyldiethanolamine, dimethylethanolamine, triethanolamine, triethylamine and N-methylmorpholine; twenty

(2) aromatic amines such as amylparadimethylaminobenzoate, 2-n-butoxyethyl-4- (dimethylamino) benzoate, 2- (dimethylamino) ethylbenzoate, ethyl-4- (dimethylamino) benzoate and 2-ethylhexyl-4- (dimethylamino) benzoate;

(3) (meth) acrylated amines such as dialkylamino alkyl (meth) acrylates (for example, diethylaminoethylacrylate) or N-morpholinoalkyl- (meth) acrylates (for example, N-morpholinoethyl acrylate); Y

(4) amides or ureas.

Preferred co-initiators are aminobenzoates.

A preferred initiator system is 2,2'-bis (o-chlorophenyl) -4,4 ', 5,5'-tetraphenyl- (7CI, 8CI) 4,4'-Bi-4H-imidazole corresponding to the chemical formula : 30

in the presence of a co-initiator such as 2-mercapto benzoxazole.

Another preferred type of initiator is an oxime ester. A suitable example has the chemical formula:

 5

A preferred amount of initiator is 0.3-50% by weight of the total weight of the curable liquid and more preferably 1-15% by weight of the total weight of the inkjet ink curable.

The irradiation with actinic radiation can be done in two stages by changing the wavelength or intensity. In such cases it is preferred to use two two types of photo-initiator together.

Inhibitors

Suitable polymerization inhibitors include phenol-type antioxidants, sterile hindrance amine light stabilizers, phosphorus-type antioxidants, hydroquinone monomethyl ether normally used in (meth) acrylate monomers and hydroquinone, t-butylcatechol and pyrogallol can also be used.

Suitable commercially available inhibitors are, for example, SumilizerTM GA-80, SumilizerTM GM and SumilizerTM GS produced by Sumitomo Chemical Co. Ltd .; GenoradTM 16, GenoradTM 18 and GenoradTM 20 of Rahn AG; 20 IrgastabTM UV10 and IrgastabTM UV22, TinuvinTM 460 and CGS20 from Ciba Specialty Chemicals; UV range of FloorstabTM (UV-1, UV-2, UV-5 and UV-8) from Kromachem Ltd, S range of AdditolTM (S100, S110, S120 and S130) from Cytec Surface Specialties.

However, most preferably, the inhibitor is a polymerizable inhibitor. 25

Since the excessive addition of these polymerization inhibitors will decrease the sensitivity of the ink to cure, it is preferred that the amount capable of preventing polymerization be determined before mixing. The amount of a polymerization inhibitor is preferably less than 2% by weight of the total ink. 30

Surfactants

The surfactant or surfactants can be anionic, cationic, nonionic or zwitterionic and are usually added in a total amount of less than 20% by weight based on the total weight of the inkjet ink and particularly in a total of less than 10% in weight based on the total weight of the jet ink.

Suitable surfactants include fluorinated surfactants, fatty acid salts, ester salts of a higher alcohol, alkylbenzene sulfonate salts, sulfosuccinate ester salts and phosphate ester salts of a higher alcohol (for example, sodium dodecylbenzenesulfonate and dioctyl sulfosuccinate ), ethylene oxide adducts of a higher alcohol, ethylene oxide adducts of an alkylphenol, ethylene oxide adducts of a fatty acid ester of polyhydric alcohol and acetylene glycol and ethylene oxide adducts thereof (for example, polyoxyethylene nonylphenyl 10 ether and SURFYNOL ™ 104, 104H, 440, 465 and TG available from AIR PRODUCTS CHEMICALS INC.).

For non-aqueous jet injection inks, the preferred surfactants are selected from fluorine surfactants (such as fluorinated hydrocarbons) and silicone surfactants. Silicones are typically siloxanes and can be alkoxylated, modified with polyether, functional hydroxy modified with polyether, modified with amine, modified with epoxy and other modifications or combinations thereof. Preferred siloxanes are polymeric, for example polydimethylsiloxanes.

A fluorinated or silicone compound can be used as a surfactant in radiation-jet inkjet inks, however, a crosslinkable surfactant would be preferred. Therefore, it is preferred to use a copolymerizable monomer having active surface effects, for example, polyacrylate copolymers, silicone modified acrylates, silicone modified methacrylates, acrylated siloxanes, polyether modified acrylic siloxanes, fluorinated acrylates and fluorinated methacrylates; These acrylates can be mono-, di-, tri- (meth) acrylates or more functional.

Surfactants are known for use in jet injection inks to reduce the surface tension of the ink and to reduce the contact angle on the substrate, that is, to improve the wetting of the substrate by the ink. On the other hand, the expellable liquid must meet a rigorous performance criterion to be properly ejected with high precision and reliability and for an extended period of time. In order to achieve the wetting of the substrate by the ink and a high ejection performance, typically, the surface tension of the ink is reduced by the addition of one or more surfactants. In the case of curable inkjet inks, however, the surface tension of the inkjet ink is determined not only by the amount and type of surfactant, but also by polymerizable compounds, polymeric dispersants and other additives in The ink composition.

Depending on the application, a surfactant with a high, low or intermediate dynamic surface tension can be used. Silicone surfactants are generally known to have dynamic surface tensions while fluorinated surfactants are known to have higher dynamic surface tensions.

Useful commercially available fluorinated surfactants are, for example, the DUPONT Zonyl ™ range of fluorine surfactants and the 3 Fluorad ™ range of 3M fluorine surfactants. Other fluorinated surfactants are described, for example, in EP 1412438 A (3M).

Silicone surfactants are usually preferred in curable jet injection inks, especially reactive silicone surfactants, which are capable of polymerizing together with the polymerizable compounds during the curing step.

Useful commercially available silicone surfactants are usually polysiloxane surfactants, especially polyether modified polysiloxanes, preferably with one or more acrylate functions to become polymerizable. twenty

Examples of useful commercially available silicone surfactants are those supplied by BYK CHEMIE GMBH (including BykTM-302, 307, 310, 331, 333, 341, 345, 346, 347, 348, UV3500, UV3510 and UV3530), those supplied by TEGO CHEMIE SERVICE (including Tego RadTM 2100, 2200N, 2250, 2300, 2500, 2600 and 2700), EbecrylTM 1360 a polysiloxane hexaacrylate 25 from CYTEC INDUSTRIES BV and the 3000 series from EfkaTM (including EfkaTM-3232 and EfkaTM-3883) from EFKA CHEMICALS BV

Binders

The inkjet inks of the inkjet ink cartridge according to the present invention may comprise a binder resin. The binder functions as a viscosity controlling agent and also provides fixability with respect to a substrate, for example a polyvinyl chloride substrate. Preferably, the binder has a good solubility in the solvent or solvents.

The non-aqueous inkjet ink compositions 35 preferably comprise a binder resin. The binder functions as a viscosity controlling agent and also provides fixability with respect to the polymer resin substrate, for example a polyvinyl chloride substrate, also called a vinyl substrate. The binder should be selected as having a good solubility in the solvent or solvents.

Suitable examples of binder resins include acrylic resins, modified acrylic resins, acrylic styrene resins, acrylic copolymers, acrylate resins, aldehyde resins, rosins, rosin esters, 5 modified rosins and modified rosin resins, acetyl polymers, resin acetal such as polyvinyl butyral, ketone resins, phenolic resins and modified phenolic resins, maleic resins and modified maleic resins, terpene resins, polyester resins, polyamide resins, polyurethane resins, epoxy resins, vinyl resins, copolymer resins 10 of vinyl chloride-vinyl acetate, cellulose-type resins such as nitrocellulose, cellulose acetopropionate and cellulose acetate butyrate and vinyl toluene-α-methyl ethylene copolymer resin. These binders can be used alone or in a mixture thereof. The binder is preferably a thermoplastic film-forming resin. fifteen

The amount of binder resin in the inkjet ink is preferably in the range of 0.1 to 30% by weight, more preferably 1 to 20% by weight, most preferably 2 to 10% by weight based on the Total weight of jet ink.

Humectants 20

If the jet injection inks contain organic solvents or water, preferably at least one humectant is present in the inks to prevent clogging of the nozzle, due to its ability to decrease the ink evaporation rate.

Suitable humectants include triacetin, N-methyl-2-pyrrolidone, glycerol, urea, thiourea, ethylene urea, alkyl urea, alkyl thiourea, dialkyl urea and dialkyl thiourea, diols, including ethanediols, propanediols, propanediols, butanediols, pentanediols, pentanediols hexanediols; glycols, which include propylene glycol, polypropylene glycol, ethylene glycol, polyethylene glycol, diethylene glycol, tetraethylene glycol, and mixtures and derivatives thereof. Preferred humectants are triethylene glycol mono butyl ether, glycerol and 1,2-hexanediol. The humectant is preferably added to the inkjet ink formulation in an amount of 0.1 to 40% by weight of the formulation, more preferably 0.1 to 10% by weight of the formulation and most preferably about 4.0 to 6.0% by weight. 35

Other additives

The inkjet inks of the inkjet ink cartridge according to the present invention may include other additives, such as buffering agents, anti-molding agents, pH adjusting agents, electrical conductivity adjusting agents, chelating agents, anti-corrosion agents, light stabilizers, dendrimers, polymers, crosslinking agents, soluble electrolytes as conductivity aids, sequestering agents and chelating agents, compounds for introducing additional safety features and the like. Such additives may be included in the color inkjet inks of the inkjet ink cartridge according to the present invention in any effective amount, as desired.

Compounds for introducing additional safety features 10 include a fluorescent compound, a phosphorescent compound, a thermochromic compound, an iridescent compound and a magnetic particle. Suitable UV fluorescents and phosphorescent compounds include HUMEYWELL LUMILUX ™ luminescent pigments, CIBAGEIGY UVITEX ™ OB, KEYFLUOR ™ dyes and KEYSTONE pigments and SYNTHEGEN fluorescent dyes.

The color inkjet inks of the inkjet ink cartridge according to the present invention may additionally comprise conductive or semiconductor polymers, such as polyanilines, polypropyls, polythiophenes such as poly (ethylenedioxythiophene) 20 (PEDOT), poly ( substituted or unsubstituted phenylenevinylenes (PPV) such as PPV and MEH-PPV, polyfluorenes such as PF6, etc.

Preparation of pigmented inkjet inks

The average particle size and distribution is an important feature for jet injection inks. The jet ink can be prepared by precipitating or grinding the pigment in the dispersion medium in the presence of the dispersant.

Mixing apparatus may include a pressure kneader, an open kneader, a planetary mixer, a dissolution vessel and a Dalton Universal Mixer. Suitable mixing and dispersion apparatus 30 are a ball mill, pearl mill, colloid mill, high speed disperser, double rollers, a glass mill, a paint conditioner and triple rollers. Dispersions can also be prepared using ultrasonic energy.

Many different types of materials can be used as grinding media, such as glass, ceramics, metals and plastics. In a preferred embodiment, the grinding means may comprise particles, preferably spherically in substantially shaped form, for example, beads consisting basically of a polymeric resin or zirconium oxide beads stabilized with yttrium.

In the mixing, grinding and dispersion process, each process is carried out with refrigeration to prevent heat accumulation and for radiation curable inkjet inks as much as possible with 5 light conditions in which actinic radiation has been substantially excluded.

The inkjet ink may contain more than one pigment, the inkjet ink may be prepared using separate dispersions for each pigment, or alternatively various pigments 10 may be mixed and co-ground in the preparation of the dispersion.

The dispersion process can be carried out in a continuous, discontinuous or semi-discontinuous manner.

The preferred amounts and proportions of the milling ingredients will vary widely depending on the specific materials and the intended applications. The contents of the milling mixture comprise mill milling and grinding media. Mill milling comprises pigment, polymeric dispersant and a liquid excipient. For jet injection inks, the pigment is normally present in mill milling from 1 to 50% by weight, excluding milling media. The weight ratio of pigment to the polymer dispersant is 20: 1 to 1: 2.

The grinding time can vary widely and depends on the pigment, the selected mechanical medium and the conditions of permanence, the desired initial and final particle size, etc. In the present invention, pigment dispersions with an average particle size of less than 100 nm can be prepared.

After grinding is completed, the grinding media is separated from the ground particulate product (either in the form of a dry or liquid dispersion) using conventional separation techniques, such as filtration, sieving through a mesh screen and the like. Sometimes the sieve is incorporated into the mill, for example, for a pearl mill. The ground pigment concentrate is preferably separated from the grinding media by filtration.

In general, it is desired to prepare the inkjet inks in the form of a concentrated mill mill, which is subsequently diluted to give the appropriate concentration for use in the inkjet printing system. This technique allows the preparation of a greater amount of pigmented ink from the equipment. By dilution, the inkjet ink is adjusted to the viscosity, surface tension, color, hue, saturation density and print area coverage desired for the particular application.

EXAMPLES 5

materials

All materials used in the following examples were readily available from conventional sources such as Aldrich Chemical Co. (Belgium) and Acros (Belgium) unless otherwise specified.

PV19 is an abbreviation used for Hostaperm ™ Red E5B 02, a Pigment 10 violet I.C. CLARIANT 19.

PB15: 3 (A) is an abbreviation used for Hostaperm ™ Blue B4G, a Blue Pigment I.C. CLARIANT 15: 3.

PB15: 3 (B) is an abbreviation used for Sunfast ™ Blue 249-1284, a Blue Pigment I.C. SUN CHEMICAL 15: 3. fifteen

PY150 is an abbreviation used for Chromophtal ™ Yellow LA, a Yellow Pigment I.C. 150 of CIBA SPECIALTY CHEMICALS.

PBlack7 is Special Black ™ 550, a carbon black available in DEGUSSA TR52 is TIOXIDE TR 52 ™, a superficially modified titanium dioxide from HUNTSMAN CHEMICAL GROUP. twenty

SOLSPERSE ™ 35000, a NOVEON polyethyleneimine-polyester hyperdispersant.

S39000 is an abbreviation for SOLSPERSE ™ 39000, a polyethyleneimine-polyester hyperdispersant from NOVEON.

S5000 is an abbreviation for Solsperse ™ 5000, a synergistic dispersion of sulfonated copper phthalocyanine from NOVEON.

SOLSPERSE ™ 36000 is a polymeric dispersant for TiO2 from NOVEON.

Genorad ™ 16 is a polymerization inhibitor of RAHN AG.

DPGDA is SARTOMER dipropylene glycol acrylate.

SR9003 is an abbreviation for Sartomer ™ SR9003, a propoxylated neopentyl glycol diacrylate monomer available from SARTOMER.

VEEA is 2- (2-vinyloxyethoxy) ethyl acrylate from NIPPON SHOKUBAI.

IBOA is isobornyl acrylate available as Sartomer 506D in SARTOMER.

TMPTA is Trimethylolpropane Triacrylate available as SR351 in SARTOMER. 35

Esacure ™ KT046 is a mixture of trimethylbenzoyldiphenylphosphine oxide, alpha-hydroxyketone and benzophenone derivatives available at FRATELLI LAMBERTI SPA.

Darocur ™ TPO is 2,4,6-trimethylbenzoyl diphenyl phosphinoxide from CIBA SPECIALTY CHEMICALS.

Genocure ™ EPD is ethyl 4-dimethylaminobenzoate from RAHN AG.

Genocure ™ TPO is 2,4,6-trimethylbenzoyl diphenyl phosphinoxide from RAHN AG.

Darocur ™ ITX is an isomeric mixture of 2- and 4-isopropylthioxanthone from CIBA 5 SPECIALTY CHEMICALS.

Ebecryl ™ 350 is a polysiloxane diacrylate from CYTEC INDUSTRIES BV.

Ebecryl ™ 1360 is a polysiloxane hexaacrylate from CYTEC INDUSTRIES BV.

EBESOL is a 30% solution of Ebecryl ™ 1360 in VEEA.

TEGOGLIDE ™ 410 is a 10 GOLDSCHMIDT polysiloxane polyether copolymer.

TEGOSOL is a 30% solution of TEGOGLIDE ™ 410 in IBOA.

GENVEEA is a 50% solution of Genorad ™ 16 in VEEA.

GENIBOA is a 50% solution of Genorad ™ 16 in IBOA.

PET Black is an RPFA (Red Phototooling Film) of AGFA 15 Idealine ™ Silver Film that was exposed and developed at a maximum density of 4.2 to 4.5 as measured with a MacBeth ™ TD908 without any filter.

Measurement methods

1. Measurement of the Turbiscan ™ Stability Index

A vial with a 20 ml sample of ink was measured at 20 ° C using a Turbiscan ™ LabExpert sedimentometer together with Turbiscan ™ Easysoft (manufactured by FORMULACTION, France) that can assess sedimentation properties from intensity distributions of backscattered light and light transmitted in the height direction of a sample. Backscatter and transmission were measured at 880 nm in the 30 mm of the upper part of the vial for 13 days. The Turbiscan ™ Stability Index was calculated, in which a higher value corresponds to a less stable ink.

2. Average Particle Size of the concentrated pigment dispersion (Malvern)

The average particle size of the pigment particles in the 30 concentrated pigment dispersions was determined by photon correlation spectroscopy at a wavelength of 633 nm with a 4mW HeNe laser on a diluted sample of the pigmented inkjet ink . The particle size analyzer used was a Malvern ™ nano-S available from Goffin-Meyvis. 35

The sample was prepared by adding a drop of ink to a cuvette containing 1.5 ml of ethyl acetate and mixed until a homogeneous sample was obtained. The measured particle size is the average value of 3 consecutive measurements consisting of 6 20-second embodiments.

3. Average particle size of the inkjet ink (BI90)

The average particle size of the pigment particles in a non-aqueous inkjet ink was determined with a Brookhaven Instruments Particle Sizer BI90plus based on the dynamic light scattering principle. The ink or dispersion was diluted with ethyl acetate at a pigment concentration of 0.002% by weight. The measurement settings of the BI90plus were: 5 embodiments at 23 ° C, 90 ° angle, 635 nm wavelength and graphics = correction function.

To obtain good jet injection characteristics 10 (ejection characteristics and print quality) the average particle size of the particles dispersed in a color jet injection ink should be less than 200 nm, preferably less than 150 nm.

4. Viscosity

The viscosity of the white jet injection inks was measured using a Brookfield DV-II + viscometer at 40 ° C at 12 rotations per minute (RPM) using a CPE 40 axis, the measurement of which corresponds to a viscosity measured at 40 ° C at a shear rate of 90 s-1.

5. Substrate surface energy

The Owens-Wendt equation was used to calculate the surface energy of a substrate σs in the same manner as described in US 2005190245 (AGFA).

6. Surface tension of the inks

The surface tension of the jet injection inks was measured with a KRÜSS K9 tensiometer at 25 ° C after 60 seconds. 25

7. Measurement of CieL * a * b * parameters

The printed samples were measured with a spectrophotometer (Gretag SPM50) to determine the coordinates of the color system L * a * b * of the color difference indication method specified in the CIE (Commission International of I'Eclairage). In this case, the measurement was performed under 30 D50 light source conditions, without supply of light source filter, absolute white as reference target and a visibility angle of 2 °.

EXAMPLE 1

This example illustrates how sedimentation problems in inkjet printing can be greatly reduced by using 35 higher concentrations of TiO2 in a white inkjet ink and adjusting the temperature of the white ink based on your demand for printing. .

White pigment dispersion preparation

 Concentrated white pigment dispersions W1 and W2 were prepared according to Table 3.

Table 3

 % by weight of:

 W1 W2

 TR52

 50.0 50.0

 SolsperseTM 36000

 10.0 10.0

 GenoradTM 16

 1.0 1.0

 SEE

 39.0 ---

 IBOA

 --- 39.0

 5

The W1 concentrated pigment dispersion was prepared by mixing 500.0 g of the white TR52 pigment, 20.0 g of a 50% solution of the Genorad ™ 16 inhibitor in VEEA and 333.3 g of a 30% solution of the Solsperse polymer dispersant ™ 36000 in VEEA for 30 minutes using a DISPERLUX ™ Laboratory Dissolver YELLOW075 from DISPERLUX SARL, 10 Luxembourg. This mixture was subsequently ground in an Eiger Lab Bead mill (from EIGER TORRANCE Ltd.) using 1-1.6mm diameter stabilized zirconium oxide beads ("high wear resistant zirconia grinding media" from TOSOH Co.). The pearl mill is loaded at 52% with the milling beads and cooled with water during the milling at 1500 rpm for 5 minutes. The W1 concentrated pigment dispersion had an average particle size of 317 nm measured with a Malvern ™ nano-S particle size analyzer.

The W2 concentrated pigment dispersion was prepared by mixing 500.0 g of the white TR52 pigment, 20.0 g of a 50% solution of the Genorad ™ 16 inhibitor 20 in IBOA and 333.3 g of a 30% solution of the polymeric dispersant Solsperse ™ 36000 in IBOA for 30 minutes using a KOTHOFF MS1 dispersion system from Hans Kothoff, Apparate-und Maschinenbau, Rodenkirchen, Germany. The W2 concentrated pigment dispersion had an average particle size of 335 nm measured with a Malvern ™ nano-S particle size analyzer.

Preparation of white inkjet inks

The curable white inkjet inks INK-1 to INK-6 were prepared from the dispersion of concentrated pigments W1 and W2 by adding the remaining components with stirring at 20 ° C to obtain a composition as shown in Table 4.

Table 4

 % by weight of

 INK-1 INK-2 INK-3 INK-4 INK-5 INK-6

 W1

 34.0 51.0 68.0 --- --- ---

 W2

 --- --- --- 34.0 51.0 68.0

 IBOA

 --- --- --- 53.7 36.7 19.7

 SEE

 26.9 13.9 0.8 --- --- ---

 TMPTA

 26.8 22.8 18.9 --- --- ---

 EsacureTM KTO46

 10.0 10.0 10.0 10.0 10.0 10.0

 EBESOL

 1.0 1.0 1.0 --- --- ---

 TEGOSOL

 --- --- --- 1.0 1.0 1.0

 GENVEEA

 1.3 1.3 1.3 --- --- ---

 GEN I BOA

 --- --- --- 1.3 1.3 1.3

Evaluation

The viscosity of the inkjet inks INK-1 to INK-6 was measured at 40 ° C using a Brookfield DV-II + viscometer and is indicated in Table 5 5. It can be seen that the viscosity increases with an increase in the TiO2 content .

Table 5

 ink

 % by weight of TiO2 Viscosity (mPa.s)

 INK-1

 17 11

 INK-2

 26 16

 INK-3

 34 20

 INK-4

 17 11

 INK-5

 26 16

 INK-6

 34 24

The viscosity of inks TINTA-2, TINTA-3, TINTA-5 and TINTA-6 can be reduced by increasing the temperature of the ink.

Table 6

 Temperature

 Viscosity (mPa.s)

 INK-2

 INK-3 INK-5 INK-6

 40 ° C

 16 20 16 24

 50ºC

 12 --- 12 ---

 55 ° C

 11 15 11 ---

 60ºC

 --- 11 --- 14

 65 ° C

 --- --- --- 12

The Turbiscan ™ LabExpert sedimentometer was used to determine the sedimentation rate. From Table 7, it is clear that the more concentrated inks TINTA-2, TINTA-3, TINTA-5 and TINTA-6 showed a lower value for the Turbiscan Stability Index and therefore were much more stable. 5

Table 7

 ink

 Turbiscan Stability Index

 INK-1

 13

 INK-2

 5

 INK-3

 6

 INK-4

 19

 INK-5

 10

 INK-6

 10

Preparation and coating of white ink mixtures

The inkjet inkjet inks TINTA-2 and TINTA-3, respectively inkjet inkjet inks TINTA-5 and TINTA-6, were diluted with 10 monomers, surfactants, photoinitiators and stabilizers to obtain the same composition as the inkjet ink inkjet ink-1, respectively inkjet inkjet ink ink-4, thus allowing a representative comparison between the inks with an equal content of 17% by weight of TiO2 based on the total weight of the ink. fifteen

To simulate the sedimentation conditions in a printer, the white ink mixtures mentioned above were prepared after 1 hour, 6 hours, 24 hours, 1 week, 2 weeks and 9 weeks of storage without stirring at room temperature, taking samples with a pipette in the upper part of the containers of the inks TINTA-2 and 20 TINTA-3 and TINTA-5 and TINTA-6 and subsequently diluting them with the other components with agitation of them for 5 minutes. The samples of TINTA-1 and TINTA-4 were also taken with a pipette on the top of their container after 1 hour, 6 hours, 24 hours, 1 week, 2 weeks and 9 weeks of storage without stirring at room temperature and then they were stirred for 5 minutes before the test.

The inkjet inks TINTA-1, TINTA-4 and the white ink mixtures were each coated on a Black PET substrate using a bar applicator and a 10 µm wire rod. Each coated layer was cured using a Fusion DRSE-120 conveyor, equipped with a 30 Fusion VPS / 1600 lamp (bulb D), which transported the samples under the UV lamp on a conveyor belt at a speed of 20 m / min.

The luminosity values of the white coated layers were determined and are indicated in Table 8.

Table 8 5

 After storage at 20 ° C for:

 L brightness value for white ink:

 INK-1

 TINTA-2 diluted TINTA-3 diluted TINTA-4 TINTA-5 diluted TINTA-6 diluted

 1 hour

 67 67 67 63 68 68

 6 hours

 65 68 69 63 67 66

 24 hours

 66 68 69 63 66 65

 1 week

 45 60 67 57 64 69

 2 weeks

 12 24 64 47 52 66

 9 weeks

 10 31 57 13 47 52

Table 8 illustrates that the diluted white ink blends after more than one week of storage in a jet injection printer from the upper concentrated inks TINTA-2 and TINTA-3, respectively TINTA-5 and TINTA-6, they continued to show good quality of 10 images, while inkjet inks TINTA-1 and TINTA-4 continued to deteriorate rapidly.

The undiluted jet injection inks TINTA-2, TINTA-3, TINTA-5 and TINTA-6 were coated and cured in the same manner as indicated above and compared with the inkjet inks TINTA-1 15 and INK-4. The CieL * a * b * parameters were determined for all TINTA-1 to TINTA-6 coated inks, as well as for the uncoated Black PET substrate (without ink). Another advantage that becomes evident from the Cielab measurements in Table 9 is that less white ink is required to reach a certain level of opacity. The thinner layers are not only economically interesting, but show different physical properties, such as greater flexibility.

Table 9

 Parameter CieL * a * b *

 Without ink INK-1 INK-2 INK-3 INK-4 INK-5 INK-6

 L *

 9 68 75 77 63 72 74

 to*

 1.7 -3.1 -3.0 -3.0 -3.6 -3.3 -3.1

 b *

 1.2 -5.4 -5.2 -5.4 -7.4 -6.0 -5.6

EXAMPLE 2

This example shows a jet inkjet ink cartridge that has been optimized for ejection with Nova 256/80 AAA printheads (available in FUJIFILM DIMATIX) at an ejection temperature of 5 40 ° C.

The printheads in the jet injection printers are all operating normally at the same temperature, which simplifies not only the requirements for a temperature control system, but also results in better image quality in the printing of 10 radiation curable jet injection since the cure speed is influenced by differences in ink temperature.

The multi-density inkjet ink cartridge consists of a neutral black ink (K), a magenta ink (M) and a light magenta ink (LM), a cyan ink (C) and a light cyan ink (LC) and a Yellow ink (Y) 15 composed as shown in Table 10 and white inkjet ink TINTA-3 (composition seen in Example 1).

Table 10

 % by weight of ink

 K M LM C LC Y

 DPGDA

 60.92 60.80 32.94 23.79 33.36 41.20

 SR9003

 20.00 20.00 50.00 60.00 50.00 41.40

 PBlack7

 1.54 --- --- --- --- ---

 PV19

 0.55 3.60 0.51 --- --- ---

 PB15: 3 (A)

 0.55 --- --- --- --- ---

 PB15: 3 (B)

 --- --- --- 1.17 0.17 ---

 PY150

 - --- --- --- --- 1.80

 S39000

 2.64 1.80 0.25 1.17 0.17 1.80

 S 5000

 --- --- --- 0.06 0.01 ---

 Darocur ™ ITX

 5.00 5.00 --- 5.00 --- 5.00

 Darocur ™ TPO

 --- --- 10.00 --- 10.00 ---

 Genocure ™ EPD

 7.50 7.50 5.00 7.50 5.00 7.50

 Ebecryl ™ 350

 0.30 0.30 0.30 0.30 0.30 0.30

 Genorad ™ 16

 1.00 1.00 1.00 1.00 1.00 1.00

 Viscosity at 40 ° C (mPa.s)

 11 12 11 10 10 10

 Surface tension at 25 ° C (mN / m)

 24.2 24.0 24.0 24.5 24.2 24.1

The dispersion quality of the color pigments in the jet injection inks tends to deteriorate when the ink is maintained at higher temperatures for a long period of time. The average particle size of the inks in the inkjet ink cartridge of Table 10 was determined after preparation and again after a week heat treatment at 80 ° C. The results are given in Table 11. 5

Table 11

 Measure later

 Average particle size in nm (BI90)

 K

 M LM C LC Y

 preparation

 134 140 134 103 103 202

 1 week at 80ºC

 230 291 209 112 109 204

From Table 11, it is clear that, in particular, the dispersion stability of the black and magenta inkjet inks of this ink cartridge is affected by prolonged storage at a higher temperature. Therefore, these color inks are preferably used with printheads operating at a lower temperature, for example 40 ° C. In order to obtain reduced sedimentation problems with the white inkjet ink, it is necessary to eject the white inkjet ink at a temperature greater than about 60 ° C (see Table 6) because the viscosity plays an important role in The ejection performance of a jet ink.

Claims (14)

1. An inkjet printing method comprising the steps of: a) providing a white inkjet ink and at least one color inkjet ink to a jet inkjet printer; Y b) eject the white inkjet ink at a temperature higher than the color inkjet ink on an ink receiver, wherein the difference in the ejection temperature between the white inkjet ink 10 and the color inkjet ink is at least 5 ° C. 2. The inkjet printing method according to claim 1, wherein the temperature of the white ink in a printhead is reduced by at least 5 ° C when the images being printed do not require white ink or when The jet injection printer is not used for more than 24 hours. 3. The inkjet printing method according to claim 2, wherein the temperature of the printhead of the color jet ink remains at its ejection temperature. twenty 4. The inkjet printing method according to any one of claims 1 to 3 which comprises surface printing or non-pressure of the white ink on a transparent or translucent substrate to form a reflection image. 5. The inkjet printing method according to any one of claims 1 to 4, wherein a color inkjet ink is ejected onto a partially cured white inkjet ink. 6. A jet injection printer comprising a means for controlling the temperature and optionally also counter-pressure, 30 independently for a white jet inkjet printhead and a jet inkjet printhead. color. 7. The inkjet printer according to claim 6 comprising a means for controlling the counter-pressure 35 independently of a white jet inkjet printhead and a jet inkjet printhead. color. 8. The inkjet printer according to claim 6 or 7 comprising a color inkjet ink cartridge that includes a white ink containing a pigment with a refractive index greater than 1.60 and at least one color inkjet ink characterized in that the viscosity of the white inkjet ink 5 is at least 4 mPa.s greater than the viscosity of the color inkjet ink at which the viscosity is measured at 40 ° C with a Brookfield DV-II + Pro at 12 rotations per minute. 9. The inkjet printer according to claim 8, wherein the pigment with a refractive index greater than 10 1.60 is a titanium dioxide, preferably rutile. 10. The inkjet printer according to claim 9, wherein the average particle size of the titanium dioxide measured with photon correlation spectroscopy at a wavelength of 633 nm is between 0.2 and 0.5 µm fifteen 11. The inkjet printer according to any one of claims 8 to 10, wherein the white inkjet ink comprises at least 26% by weight of a white pigment based on the total weight of white inkjet ink. 12. The inkjet printer according to any one of claims 8 to 11, wherein the white inkjet ink is curable by heat, radiation and / or electron jet. 13. The inkjet printer according to any one of claims 8 to 12, wherein the white jet ink comprises a polymerizable compound selected from the group consisting of isobornyl acrylate, acrylate phenoxyethyl, tetrahydrofurfuryl acrylate, 2- (2-vinyloxyethoxy) ethyl (N) vinylcaprolactam (meth) acrylate. 14. Use of temperature control in an inkjet printer to reduce sedimentation of a pigment with a refractive index greater than 1.60 in a white inkjet ink. 30